Convert "path.*" and "pidfile" to new settings infra

88 files changed, 350 insertions, 260 deletions

diff --git a/core/src/main/java/org/elasticsearch/bootstrap/Security.java b/core/src/main/java/org/elasticsearch/bootstrap/Security.java
index 43ad73b5de..dc89ce3cb1 100644
--- a/core/src/main/java/org/elasticsearch/bootstrap/Security.java
+++ b/core/src/main/java/org/elasticsearch/bootstrap/Security.java
@@ -241,26 +241,26 @@ final class Security {
      */
     static void addFilePermissions(Permissions policy, Environment environment) {
         // read-only dirs
-        addPath(policy, "path.home", environment.binFile(), "read,readlink");
-        addPath(policy, "path.home", environment.libFile(), "read,readlink");
-        addPath(policy, "path.home", environment.modulesFile(), "read,readlink");
-        addPath(policy, "path.plugins", environment.pluginsFile(), "read,readlink");
-        addPath(policy, "path.conf", environment.configFile(), "read,readlink");
-        addPath(policy, "path.scripts", environment.scriptsFile(), "read,readlink");
+        addPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.binFile(), "read,readlink");
+        addPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.libFile(), "read,readlink");
+        addPath(policy, Environment.PATH_HOME_SETTING.getKey(), environment.modulesFile(), "read,readlink");
+        addPath(policy, Environment.PATH_PLUGINS_SETTING.getKey(), environment.pluginsFile(), "read,readlink");
+        addPath(policy, Environment.PATH_CONF_SETTING.getKey(), environment.configFile(), "read,readlink");
+        addPath(policy, Environment.PATH_SCRIPTS_SETTING.getKey(), environment.scriptsFile(), "read,readlink");
         // read-write dirs
         addPath(policy, "java.io.tmpdir", environment.tmpFile(), "read,readlink,write,delete");
-        addPath(policy, "path.logs", environment.logsFile(), "read,readlink,write,delete");
+        addPath(policy, Environment.PATH_LOGS_SETTING.getKey(), environment.logsFile(), "read,readlink,write,delete");
         if (environment.sharedDataFile() != null) {
-            addPath(policy, "path.shared_data", environment.sharedDataFile(), "read,readlink,write,delete");
+            addPath(policy, Environment.PATH_SHARED_DATA_SETTING.getKey(), environment.sharedDataFile(), "read,readlink,write,delete");
         }
         for (Path path : environment.dataFiles()) {
-            addPath(policy, "path.data", path, "read,readlink,write,delete");
+            addPath(policy, Environment.PATH_DATA_SETTING.getKey(), path, "read,readlink,write,delete");
         }
         for (Path path : environment.dataWithClusterFiles()) {
-            addPath(policy, "path.data", path, "read,readlink,write,delete");
+            addPath(policy, Environment.PATH_DATA_SETTING.getKey(), path, "read,readlink,write,delete");
         }
         for (Path path : environment.repoFiles()) {
-            addPath(policy, "path.repo", path, "read,readlink,write,delete");
+            addPath(policy, Environment.PATH_REPO_SETTING.getKey(), path, "read,readlink,write,delete");
         }
         if (environment.pidFile() != null) {
             // we just need permission to remove the file if its elsewhere.
diff --git a/core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java b/core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java
index e220fcf5de..13a9e880cc 100644
--- a/core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java
+++ b/core/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java
@@ -38,6 +38,7 @@ import org.elasticsearch.common.logging.ESLoggerFactory;
 import org.elasticsearch.discovery.DiscoverySettings;
 import org.elasticsearch.discovery.zen.ZenDiscovery;
 import org.elasticsearch.discovery.zen.elect.ElectMasterService;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.gateway.GatewayService;
 import org.elasticsearch.gateway.PrimaryShardAllocator;
 import org.elasticsearch.index.IndexSettings;
@@ -168,5 +169,15 @@ public final class ClusterSettings extends AbstractScopedSettings {
         IndexSettings.QUERY_STRING_ANALYZE_WILDCARD,
         IndexSettings.QUERY_STRING_ALLOW_LEADING_WILDCARD,
         PrimaryShardAllocator.NODE_INITIAL_SHARDS_SETTING,
-        ScriptService.SCRIPT_CACHE_SIZE_SETTING)));
+        ScriptService.SCRIPT_CACHE_SIZE_SETTING,
+        Environment.PATH_CONF_SETTING,
+        Environment.PATH_DATA_SETTING,
+        Environment.PATH_HOME_SETTING,
+        Environment.PATH_LOGS_SETTING,
+        Environment.PATH_PLUGINS_SETTING,
+        Environment.PATH_REPO_SETTING,
+        Environment.PATH_SCRIPTS_SETTING,
+        Environment.PATH_SHARED_DATA_SETTING,
+        Environment.PIDFILE_SETTING
+    )));
 }
diff --git a/core/src/main/java/org/elasticsearch/common/settings/Setting.java b/core/src/main/java/org/elasticsearch/common/settings/Setting.java
index 0fc5b062e6..b67ba26c09 100644
--- a/core/src/main/java/org/elasticsearch/common/settings/Setting.java
+++ b/core/src/main/java/org/elasticsearch/common/settings/Setting.java
@@ -309,6 +309,10 @@ public class Setting<T> extends ToXContentToBytes {
         return new Setting<>(key, (s) -> Long.toString(defaultValue), (s) -> parseLong(s, minValue, key), dynamic, scope);
     }
 
+    public static Setting<String> simpleString(String key, boolean dynamic, Scope scope) {
+        return new Setting<>(key, "", Function.identity(), dynamic, scope);
+    }
+
     public static int parseInt(String s, int minValue, String key) {
         int value = Integer.parseInt(s);
         if (value < minValue) {
diff --git a/core/src/main/java/org/elasticsearch/env/Environment.java b/core/src/main/java/org/elasticsearch/env/Environment.java
index b6453a4707..65d62bd9e3 100644
--- a/core/src/main/java/org/elasticsearch/env/Environment.java
+++ b/core/src/main/java/org/elasticsearch/env/Environment.java
@@ -23,6 +23,7 @@ import org.apache.lucene.util.Constants;
 import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.common.SuppressForbidden;
 import org.elasticsearch.common.io.PathUtils;
+import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Settings;
 
 import java.io.IOException;
@@ -33,6 +34,9 @@ import java.nio.file.FileStore;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.function.Function;
 
 import static org.elasticsearch.common.Strings.cleanPath;
 
@@ -43,6 +47,15 @@ import static org.elasticsearch.common.Strings.cleanPath;
 // TODO: move PathUtils to be package-private here instead of
 // public+forbidden api!
 public class Environment {
+    public static final Setting<String> PATH_HOME_SETTING = Setting.simpleString("path.home", false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PATH_CONF_SETTING = Setting.simpleString("path.conf", false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PATH_SCRIPTS_SETTING = Setting.simpleString("path.scripts", false, Setting.Scope.CLUSTER);
+    public static final Setting<List<String>> PATH_DATA_SETTING = Setting.listSetting("path.data", Collections.emptyList(), Function.identity(), false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PATH_LOGS_SETTING = Setting.simpleString("path.logs", false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PATH_PLUGINS_SETTING = Setting.simpleString("path.plugins", false, Setting.Scope.CLUSTER);
+    public static final Setting<List<String>> PATH_REPO_SETTING = Setting.listSetting("path.repo", Collections.emptyList(), Function.identity(), false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PATH_SHARED_DATA_SETTING = Setting.simpleString("path.shared_data", false, Setting.Scope.CLUSTER);
+    public static final Setting<String> PIDFILE_SETTING = Setting.simpleString("pidfile", false, Setting.Scope.CLUSTER);
 
     private final Settings settings;
 
@@ -95,64 +108,64 @@ public class Environment {
     public Environment(Settings settings) {
         this.settings = settings;
         final Path homeFile;
-        if (settings.get("path.home") != null) {
-            homeFile = PathUtils.get(cleanPath(settings.get("path.home")));
+        if (PATH_HOME_SETTING.exists(settings)) {
+            homeFile = PathUtils.get(cleanPath(PATH_HOME_SETTING.get(settings)));
         } else {
-            throw new IllegalStateException("path.home is not configured");
+            throw new IllegalStateException(PATH_HOME_SETTING.getKey() + " is not configured");
         }
 
-        if (settings.get("path.conf") != null) {
-            configFile = PathUtils.get(cleanPath(settings.get("path.conf")));
+        if (PATH_CONF_SETTING.exists(settings)) {
+            configFile = PathUtils.get(cleanPath(PATH_CONF_SETTING.get(settings)));
         } else {
             configFile = homeFile.resolve("config");
         }
 
-        if (settings.get("path.scripts") != null) {
-            scriptsFile = PathUtils.get(cleanPath(settings.get("path.scripts")));
+        if (PATH_SCRIPTS_SETTING.exists(settings)) {
+            scriptsFile = PathUtils.get(cleanPath(PATH_SCRIPTS_SETTING.get(settings)));
         } else {
             scriptsFile = configFile.resolve("scripts");
         }
 
-        if (settings.get("path.plugins") != null) {
-            pluginsFile = PathUtils.get(cleanPath(settings.get("path.plugins")));
+        if (PATH_PLUGINS_SETTING.exists(settings)) {
+            pluginsFile = PathUtils.get(cleanPath(PATH_PLUGINS_SETTING.get(settings)));
         } else {
             pluginsFile = homeFile.resolve("plugins");
         }
 
-        String[] dataPaths = settings.getAsArray("path.data");
-        if (dataPaths.length > 0) {
-            dataFiles = new Path[dataPaths.length];
-            dataWithClusterFiles = new Path[dataPaths.length];
-            for (int i = 0; i < dataPaths.length; i++) {
-                dataFiles[i] = PathUtils.get(dataPaths[i]);
+        List<String> dataPaths = PATH_DATA_SETTING.get(settings);
+        if (dataPaths.isEmpty() == false) {
+            dataFiles = new Path[dataPaths.size()];
+            dataWithClusterFiles = new Path[dataPaths.size()];
+            for (int i = 0; i < dataPaths.size(); i++) {
+                dataFiles[i] = PathUtils.get(dataPaths.get(i));
                 dataWithClusterFiles[i] = dataFiles[i].resolve(ClusterName.clusterNameFromSettings(settings).value());
             }
         } else {
             dataFiles = new Path[]{homeFile.resolve("data")};
             dataWithClusterFiles = new Path[]{homeFile.resolve("data").resolve(ClusterName.clusterNameFromSettings(settings).value())};
         }
-        if (settings.get("path.shared_data") != null) {
-            sharedDataFile = PathUtils.get(cleanPath(settings.get("path.shared_data")));
+        if (PATH_SHARED_DATA_SETTING.exists(settings)) {
+            sharedDataFile = PathUtils.get(cleanPath(PATH_SHARED_DATA_SETTING.get(settings)));
         } else {
             sharedDataFile = null;
         }
-        String[] repoPaths = settings.getAsArray("path.repo");
-        if (repoPaths.length > 0) {
-            repoFiles = new Path[repoPaths.length];
-            for (int i = 0; i < repoPaths.length; i++) {
-                repoFiles[i] = PathUtils.get(repoPaths[i]);
+        List<String> repoPaths = PATH_REPO_SETTING.get(settings);
+        if (repoPaths.isEmpty() == false) {
+            repoFiles = new Path[repoPaths.size()];
+            for (int i = 0; i < repoPaths.size(); i++) {
+                repoFiles[i] = PathUtils.get(repoPaths.get(i));
             }
         } else {
             repoFiles = new Path[0];
         }
-        if (settings.get("path.logs") != null) {
-            logsFile = PathUtils.get(cleanPath(settings.get("path.logs")));
+        if (PATH_LOGS_SETTING.exists(settings)) {
+            logsFile = PathUtils.get(cleanPath(PATH_LOGS_SETTING.get(settings)));
         } else {
             logsFile = homeFile.resolve("logs");
         }
 
-        if (settings.get("pidfile") != null) {
-            pidFile = PathUtils.get(cleanPath(settings.get("pidfile")));
+        if (PIDFILE_SETTING.exists(settings)) {
+            pidFile = PathUtils.get(cleanPath(PIDFILE_SETTING.get(settings)));
         } else {
             pidFile = null;
         }
diff --git a/core/src/main/java/org/elasticsearch/node/internal/InternalSettingsPreparer.java b/core/src/main/java/org/elasticsearch/node/internal/InternalSettingsPreparer.java
index 1c2ab33e9b..47f262d8d0 100644
--- a/core/src/main/java/org/elasticsearch/node/internal/InternalSettingsPreparer.java
+++ b/core/src/main/java/org/elasticsearch/node/internal/InternalSettingsPreparer.java
@@ -108,7 +108,7 @@ public class InternalSettingsPreparer {
         environment = new Environment(output.build());
 
         // we put back the path.logs so we can use it in the logging configuration file
-        output.put("path.logs", cleanPath(environment.logsFile().toAbsolutePath().toString()));
+        output.put(Environment.PATH_LOGS_SETTING.getKey(), cleanPath(environment.logsFile().toAbsolutePath().toString()));
 
         return new Environment(output.build());
     }
diff --git a/core/src/main/java/org/elasticsearch/tribe/TribeService.java b/core/src/main/java/org/elasticsearch/tribe/TribeService.java
index 78453c9eac..1a89bc2f91 100644
--- a/core/src/main/java/org/elasticsearch/tribe/TribeService.java
+++ b/core/src/main/java/org/elasticsearch/tribe/TribeService.java
@@ -45,6 +45,7 @@ import org.elasticsearch.common.regex.Regex;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
 import org.elasticsearch.discovery.DiscoveryService;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.gateway.GatewayService;
 import org.elasticsearch.node.Node;
 import org.elasticsearch.rest.RestStatus;
@@ -132,7 +133,7 @@ public class TribeService extends AbstractLifecycleComponent<TribeService> {
         for (Map.Entry<String, Settings> entry : nodesSettings.entrySet()) {
             Settings.Builder sb = Settings.builder().put(entry.getValue());
             sb.put("name", settings.get("name") + "/" + entry.getKey());
-            sb.put("path.home", settings.get("path.home")); // pass through ES home dir
+            sb.put(Environment.PATH_HOME_SETTING.getKey(), Environment.PATH_HOME_SETTING.get(settings)); // pass through ES home dir
             sb.put(TRIBE_NAME, entry.getKey());
             if (sb.get("http.enabled") == null) {
                 sb.put("http.enabled", false);
diff --git a/core/src/test/java/org/elasticsearch/action/admin/indices/TransportAnalyzeActionTests.java b/core/src/test/java/org/elasticsearch/action/admin/indices/TransportAnalyzeActionTests.java
index cb0e0fa0f7..4d53d6cd1e 100644
--- a/core/src/test/java/org/elasticsearch/action/admin/indices/TransportAnalyzeActionTests.java
+++ b/core/src/test/java/org/elasticsearch/action/admin/indices/TransportAnalyzeActionTests.java
@@ -47,7 +47,7 @@ public class TransportAnalyzeActionTests extends ESTestCase {
     @Override
     public void setUp() throws Exception {
         super.setUp();
-        Settings settings = Settings.builder().put("path.home", createTempDir().toString()).build();
+        Settings settings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
 
         Settings indexSettings = settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
diff --git a/core/src/test/java/org/elasticsearch/action/bulk/BulkProcessorIT.java b/core/src/test/java/org/elasticsearch/action/bulk/BulkProcessorIT.java
index 04b58e6b9f..70d78e78f2 100644
--- a/core/src/test/java/org/elasticsearch/action/bulk/BulkProcessorIT.java
+++ b/core/src/test/java/org/elasticsearch/action/bulk/BulkProcessorIT.java
@@ -31,6 +31,7 @@ import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.unit.ByteSizeUnit;
 import org.elasticsearch.common.unit.ByteSizeValue;
 import org.elasticsearch.common.unit.TimeValue;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESIntegTestCase;
 
 import java.util.Arrays;
@@ -156,7 +157,7 @@ public class BulkProcessorIT extends ESIntegTestCase {
     public void testBulkProcessorConcurrentRequestsNoNodeAvailableException() throws Exception {
         //we create a transport client with no nodes to make sure it throws NoNodeAvailableException
         Settings settings = Settings.builder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         Client transportClient = TransportClient.builder().settings(settings).build();
 
diff --git a/core/src/test/java/org/elasticsearch/action/search/SearchRequestBuilderTests.java b/core/src/test/java/org/elasticsearch/action/search/SearchRequestBuilderTests.java
index fc6453318c..9cef4d46e8 100644
--- a/core/src/test/java/org/elasticsearch/action/search/SearchRequestBuilderTests.java
+++ b/core/src/test/java/org/elasticsearch/action/search/SearchRequestBuilderTests.java
@@ -22,6 +22,7 @@ package org.elasticsearch.action.search;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.client.transport.TransportClient;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.elasticsearch.test.ESTestCase;
@@ -38,7 +39,7 @@ public class SearchRequestBuilderTests extends ESTestCase {
         //this client will not be hit by any request, but it needs to be a non null proper client
         //that is why we create it but we don't add any transport address to it
         Settings settings = Settings.builder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         client = TransportClient.builder().settings(settings).build();
     }
diff --git a/core/src/test/java/org/elasticsearch/bwcompat/OldIndexBackwardsCompatibilityIT.java b/core/src/test/java/org/elasticsearch/bwcompat/OldIndexBackwardsCompatibilityIT.java
index 22d93f024e..7488141379 100644
--- a/core/src/test/java/org/elasticsearch/bwcompat/OldIndexBackwardsCompatibilityIT.java
+++ b/core/src/test/java/org/elasticsearch/bwcompat/OldIndexBackwardsCompatibilityIT.java
@@ -43,6 +43,7 @@ import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.gateway.MetaDataStateFormat;
 import org.elasticsearch.index.IndexSettings;
@@ -142,13 +143,13 @@ public class OldIndexBackwardsCompatibilityIT extends ESIntegTestCase {
         Path baseTempDir = createTempDir();
         // start single data path node
         Settings.Builder nodeSettings = Settings.builder()
-            .put("path.data", baseTempDir.resolve("single-path").toAbsolutePath())
+            .put(Environment.PATH_DATA_SETTING.getKey(), baseTempDir.resolve("single-path").toAbsolutePath())
             .put("node.master", false); // workaround for dangling index loading issue when node is master
         InternalTestCluster.Async<String> singleDataPathNode = internalCluster().startNodeAsync(nodeSettings.build());
 
         // start multi data path node
         nodeSettings = Settings.builder()
-            .put("path.data", baseTempDir.resolve("multi-path1").toAbsolutePath() + "," + baseTempDir.resolve("multi-path2").toAbsolutePath())
+            .put(Environment.PATH_DATA_SETTING.getKey(), baseTempDir.resolve("multi-path1").toAbsolutePath() + "," + baseTempDir.resolve("multi-path2").toAbsolutePath())
             .put("node.master", false); // workaround for dangling index loading issue when node is master
         InternalTestCluster.Async<String> multiDataPathNode = internalCluster().startNodeAsync(nodeSettings.build());
 
diff --git a/core/src/test/java/org/elasticsearch/bwcompat/RestoreBackwardsCompatIT.java b/core/src/test/java/org/elasticsearch/bwcompat/RestoreBackwardsCompatIT.java
index 6ad05b3ff8..fec96ae236 100644
--- a/core/src/test/java/org/elasticsearch/bwcompat/RestoreBackwardsCompatIT.java
+++ b/core/src/test/java/org/elasticsearch/bwcompat/RestoreBackwardsCompatIT.java
@@ -27,6 +27,7 @@ import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.metadata.IndexTemplateMetaData;
 import org.elasticsearch.cluster.routing.allocation.decider.FilterAllocationDecider;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.snapshots.AbstractSnapshotIntegTestCase;
 import org.elasticsearch.snapshots.RestoreInfo;
@@ -64,7 +65,7 @@ public class RestoreBackwardsCompatIT extends AbstractSnapshotIntegTestCase {
             // Configure using path.repo
             return settingsBuilder()
                     .put(super.nodeSettings(nodeOrdinal))
-                    .put("path.repo", getBwcIndicesPath())
+                    .put(Environment.PATH_REPO_SETTING.getKey(), getBwcIndicesPath())
                     .build();
         } else {
             // Configure using url white list
diff --git a/core/src/test/java/org/elasticsearch/client/AbstractClientHeadersTestCase.java b/core/src/test/java/org/elasticsearch/client/AbstractClientHeadersTestCase.java
index b814cff520..3bdfc1fb7e 100644
--- a/core/src/test/java/org/elasticsearch/client/AbstractClientHeadersTestCase.java
+++ b/core/src/test/java/org/elasticsearch/client/AbstractClientHeadersTestCase.java
@@ -48,6 +48,7 @@ import org.elasticsearch.action.search.SearchAction;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.client.support.Headers;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportMessage;
@@ -90,7 +91,7 @@ public abstract class AbstractClientHeadersTestCase extends ESTestCase {
     public void initClient() {
         Settings settings = Settings.builder()
                 .put(HEADER_SETTINGS)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         threadPool = new ThreadPool("test-" + getTestName());
         client = buildClient(settings, ACTIONS);
diff --git a/core/src/test/java/org/elasticsearch/client/transport/TransportClientHeadersTests.java b/core/src/test/java/org/elasticsearch/client/transport/TransportClientHeadersTests.java
index f127ae2837..e61dab2fc4 100644
--- a/core/src/test/java/org/elasticsearch/client/transport/TransportClientHeadersTests.java
+++ b/core/src/test/java/org/elasticsearch/client/transport/TransportClientHeadersTests.java
@@ -36,6 +36,7 @@ import org.elasticsearch.common.network.NetworkModule;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.LocalTransportAddress;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.tasks.TaskManager;
 import org.elasticsearch.threadpool.ThreadPool;
@@ -83,7 +84,7 @@ public class TransportClientHeadersTests extends AbstractClientHeadersTestCase {
                 .put("node.name", "transport_client_" + this.getTestName() + "_1")
                 .put("client.transport.nodes_sampler_interval", "1s")
                 .put(HEADER_SETTINGS)
-                .put("path.home", createTempDir().toString()).build())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build())
             .addPlugin(InternalTransportService.TestPlugin.class)
             .build();
 
diff --git a/core/src/test/java/org/elasticsearch/client/transport/TransportClientIT.java b/core/src/test/java/org/elasticsearch/client/transport/TransportClientIT.java
index f01fdffd14..8ab432d6e4 100644
--- a/core/src/test/java/org/elasticsearch/client/transport/TransportClientIT.java
+++ b/core/src/test/java/org/elasticsearch/client/transport/TransportClientIT.java
@@ -24,6 +24,7 @@ import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.node.Node;
 import org.elasticsearch.node.internal.InternalSettingsPreparer;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -52,7 +53,7 @@ public class TransportClientIT extends ESIntegTestCase {
         TransportClientNodesService nodeService = client.nodeService();
         Node node = new Node(Settings.builder()
                 .put(internalCluster().getDefaultSettings())
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("node.name", "testNodeVersionIsUpdated")
                 .put("http.enabled", false)
                 .put("node.data", false)
@@ -89,7 +90,10 @@ public class TransportClientIT extends ESIntegTestCase {
     }
 
     public void testThatTransportClientSettingCannotBeChanged() {
-        Settings baseSettings = settingsBuilder().put(Client.CLIENT_TYPE_SETTING, "anything").put("path.home", createTempDir()).build();
+        Settings baseSettings = settingsBuilder()
+            .put(Client.CLIENT_TYPE_SETTING, "anything")
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
+             .build();
         try (TransportClient client = TransportClient.builder().settings(baseSettings).build()) {
             Settings settings = client.injector.getInstance(Settings.class);
             assertThat(settings.get(Client.CLIENT_TYPE_SETTING), is("transport"));
diff --git a/core/src/test/java/org/elasticsearch/client/transport/TransportClientRetryIT.java b/core/src/test/java/org/elasticsearch/client/transport/TransportClientRetryIT.java
index b28fdba8c7..e5367d1da4 100644
--- a/core/src/test/java/org/elasticsearch/client/transport/TransportClientRetryIT.java
+++ b/core/src/test/java/org/elasticsearch/client/transport/TransportClientRetryIT.java
@@ -27,6 +27,7 @@ import org.elasticsearch.cluster.ClusterName;
 import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.node.internal.InternalSettingsPreparer;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESIntegTestCase.ClusterScope;
@@ -57,7 +58,7 @@ public class TransportClientRetryIT extends ESIntegTestCase {
                 .put("node.mode", internalCluster().getNodeMode())
                 .put(ClusterName.SETTING, internalCluster().getClusterName())
                 .put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true)
-                .put("path.home", createTempDir());
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir());
 
         try (TransportClient transportClient = TransportClient.builder().settings(builder.build()).build()) {
             transportClient.addTransportAddresses(addresses);
diff --git a/core/src/test/java/org/elasticsearch/common/logging/log4j/Log4jESLoggerTests.java b/core/src/test/java/org/elasticsearch/common/logging/log4j/Log4jESLoggerTests.java
index 8f9c900907..ed8a5cffbf 100644
--- a/core/src/test/java/org/elasticsearch/common/logging/log4j/Log4jESLoggerTests.java
+++ b/core/src/test/java/org/elasticsearch/common/logging/log4j/Log4jESLoggerTests.java
@@ -27,6 +27,7 @@ import org.apache.log4j.spi.LoggingEvent;
 import org.elasticsearch.common.logging.DeprecationLogger;
 import org.elasticsearch.common.logging.ESLogger;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 import org.junit.After;
 
@@ -53,8 +54,8 @@ public class Log4jESLoggerTests extends ESTestCase {
         Path configDir = getDataPath("config");
         // Need to set custom path.conf so we can use a custom logging.yml file for the test
         Settings settings = Settings.builder()
-                .put("path.conf", configDir.toAbsolutePath())
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_CONF_SETTING.getKey(), configDir.toAbsolutePath())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         LogConfigurator.configure(settings, true);
 
diff --git a/core/src/test/java/org/elasticsearch/common/logging/log4j/LoggingConfigurationTests.java b/core/src/test/java/org/elasticsearch/common/logging/log4j/LoggingConfigurationTests.java
index 2a08dd1e55..5d90edaf7a 100644
--- a/core/src/test/java/org/elasticsearch/common/logging/log4j/LoggingConfigurationTests.java
+++ b/core/src/test/java/org/elasticsearch/common/logging/log4j/LoggingConfigurationTests.java
@@ -54,8 +54,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         try {
             Path configDir = getDataPath("config");
             Settings settings = Settings.builder()
-                    .put("path.conf", configDir.toAbsolutePath())
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_CONF_SETTING.getKey(), configDir.toAbsolutePath())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             LogConfigurator.configure(settings, true);
 
@@ -84,8 +84,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         Files.write(loggingConf, "{\"json\": \"foo\"}".getBytes(StandardCharsets.UTF_8));
         Environment environment = new Environment(
                 Settings.builder()
-                    .put("path.conf", tmpDir.toAbsolutePath())
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_CONF_SETTING.getKey(), tmpDir.toAbsolutePath())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build());
 
         Settings.Builder builder = Settings.builder();
@@ -101,8 +101,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         Files.write(loggingConf, "key: value".getBytes(StandardCharsets.UTF_8));
         Environment environment = new Environment(
                 Settings.builder()
-                    .put("path.conf", tmpDir.toAbsolutePath())
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_CONF_SETTING.getKey(), tmpDir.toAbsolutePath())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build());
 
         Settings.Builder builder = Settings.builder();
@@ -120,8 +120,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         Files.write(loggingConf2, "yaml: bar".getBytes(StandardCharsets.UTF_8));
         Environment environment = new Environment(
                 Settings.builder()
-                    .put("path.conf", tmpDir.toAbsolutePath())
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_CONF_SETTING.getKey(), tmpDir.toAbsolutePath())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build());
 
         Settings.Builder builder = Settings.builder();
@@ -138,8 +138,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         Files.write(invalidSuffix, "yml: bar".getBytes(StandardCharsets.UTF_8));
         Environment environment = new Environment(
                 Settings.builder()
-                    .put("path.conf", invalidSuffix.toAbsolutePath())
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_CONF_SETTING.getKey(), invalidSuffix.toAbsolutePath())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build());
 
         Settings.Builder builder = Settings.builder();
@@ -157,8 +157,8 @@ public class LoggingConfigurationTests extends ESTestCase {
         Files.write(loggingConf, "appender.file.type: file\n".getBytes(StandardCharsets.UTF_8), StandardOpenOption.APPEND);
         Environment environment = InternalSettingsPreparer.prepareEnvironment(
                 Settings.builder()
-                        .put("path.conf", tmpDir.toAbsolutePath())
-                        .put("path.home", createTempDir().toString())
+                        .put(Environment.PATH_CONF_SETTING.getKey(), tmpDir.toAbsolutePath())
+                        .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                         .put("logger.test_resolve_order", "TRACE, console")
                         .put("appender.console.type", "console")
                         .put("appender.console.layout.type", "consolePattern")
@@ -186,8 +186,8 @@ public class LoggingConfigurationTests extends ESTestCase {
                 StandardCharsets.UTF_8);
         Environment environment = InternalSettingsPreparer.prepareEnvironment(
                 Settings.builder()
-                        .put("path.conf", tmpDir.toAbsolutePath())
-                        .put("path.home", createTempDir().toString())
+                        .put(Environment.PATH_CONF_SETTING.getKey(), tmpDir.toAbsolutePath())
+                        .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                         .build(), new CliToolTestCase.MockTerminal());
         LogConfigurator.configure(environment.settings(), false);
         ESLogger esLogger = Log4jESLoggerFactory.getLogger("test_config_not_read");
diff --git a/core/src/test/java/org/elasticsearch/env/EnvironmentTests.java b/core/src/test/java/org/elasticsearch/env/EnvironmentTests.java
index 79f9efbb81..0a62d2829d 100644
--- a/core/src/test/java/org/elasticsearch/env/EnvironmentTests.java
+++ b/core/src/test/java/org/elasticsearch/env/EnvironmentTests.java
@@ -40,8 +40,8 @@ public class EnvironmentTests extends ESTestCase {
     public Environment newEnvironment(Settings settings) throws IOException {
         Settings build = Settings.builder()
                 .put(settings)
-                .put("path.home", createTempDir().toAbsolutePath())
-                .putArray("path.data", tmpPaths()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toAbsolutePath())
+                .putArray(Environment.PATH_DATA_SETTING.getKey(), tmpPaths()).build();
         return new Environment(build);
     }
 
@@ -49,7 +49,7 @@ public class EnvironmentTests extends ESTestCase {
         Environment environment = newEnvironment();
         assertThat(environment.resolveRepoFile("/test/repos/repo1"), nullValue());
         assertThat(environment.resolveRepoFile("test/repos/repo1"), nullValue());
-        environment = newEnvironment(settingsBuilder().putArray("path.repo", "/test/repos", "/another/repos", "/test/repos/../other").build());
+        environment = newEnvironment(settingsBuilder().putArray(Environment.PATH_REPO_SETTING.getKey(), "/test/repos", "/another/repos", "/test/repos/../other").build());
         assertThat(environment.resolveRepoFile("/test/repos/repo1"), notNullValue());
         assertThat(environment.resolveRepoFile("test/repos/repo1"), notNullValue());
         assertThat(environment.resolveRepoFile("/another/repos/repo1"), notNullValue());
diff --git a/core/src/test/java/org/elasticsearch/env/NodeEnvironmentTests.java b/core/src/test/java/org/elasticsearch/env/NodeEnvironmentTests.java
index acee455bb6..1ead12ff43 100644
--- a/core/src/test/java/org/elasticsearch/env/NodeEnvironmentTests.java
+++ b/core/src/test/java/org/elasticsearch/env/NodeEnvironmentTests.java
@@ -50,7 +50,7 @@ public class NodeEnvironmentTests extends ESTestCase {
         NodeEnvironment env = newNodeEnvironment(Settings.builder()
                 .put("node.max_local_storage_nodes", 1).build());
         Settings settings = env.getSettings();
-        String[] dataPaths = env.getSettings().getAsArray("path.data");
+        List<String> dataPaths = Environment.PATH_DATA_SETTING.get(env.getSettings());
 
         try {
             new NodeEnvironment(settings, new Environment(settings));
@@ -62,10 +62,10 @@ public class NodeEnvironmentTests extends ESTestCase {
 
         // now can recreate and lock it
         env = new NodeEnvironment(settings, new Environment(settings));
-        assertEquals(env.nodeDataPaths().length, dataPaths.length);
+        assertEquals(env.nodeDataPaths().length, dataPaths.size());
 
-        for (int i = 0; i < dataPaths.length; i++) {
-            assertTrue(env.nodeDataPaths()[i].startsWith(PathUtils.get(dataPaths[i])));
+        for (int i = 0; i < dataPaths.size(); i++) {
+            assertTrue(env.nodeDataPaths()[i].startsWith(PathUtils.get(dataPaths.get(i))));
         }
         env.close();
         assertTrue("LockedShards: " + env.lockedShards(), env.lockedShards().isEmpty());
@@ -74,11 +74,11 @@ public class NodeEnvironmentTests extends ESTestCase {
 
     public void testNodeLockMultipleEnvironment() throws IOException {
         final NodeEnvironment first = newNodeEnvironment();
-        String[] dataPaths = first.getSettings().getAsArray("path.data");
+        List<String> dataPaths = Environment.PATH_DATA_SETTING.get(first.getSettings());
         NodeEnvironment second = new NodeEnvironment(first.getSettings(), new Environment(first.getSettings()));
-        assertEquals(first.nodeDataPaths().length, dataPaths.length);
-        assertEquals(second.nodeDataPaths().length, dataPaths.length);
-        for (int i = 0; i < dataPaths.length; i++) {
+        assertEquals(first.nodeDataPaths().length, dataPaths.size());
+        assertEquals(second.nodeDataPaths().length, dataPaths.size());
+        for (int i = 0; i < dataPaths.size(); i++) {
             assertEquals(first.nodeDataPaths()[i].getParent(), second.nodeDataPaths()[i].getParent());
         }
         IOUtils.close(first, second);
@@ -355,25 +355,25 @@ public class NodeEnvironmentTests extends ESTestCase {
     public NodeEnvironment newNodeEnvironment(Settings settings) throws IOException {
         Settings build = Settings.builder()
                 .put(settings)
-                .put("path.home", createTempDir().toAbsolutePath().toString())
-                .putArray("path.data", tmpPaths()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toAbsolutePath().toString())
+                .putArray(Environment.PATH_DATA_SETTING.getKey(), tmpPaths()).build();
         return new NodeEnvironment(build, new Environment(build));
     }
 
     public NodeEnvironment newNodeEnvironment(String[] dataPaths, Settings settings) throws IOException {
         Settings build = Settings.builder()
                 .put(settings)
-                .put("path.home", createTempDir().toAbsolutePath().toString())
-                .putArray("path.data", dataPaths).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toAbsolutePath().toString())
+                .putArray(Environment.PATH_DATA_SETTING.getKey(), dataPaths).build();
         return new NodeEnvironment(build, new Environment(build));
     }
 
     public NodeEnvironment newNodeEnvironment(String[] dataPaths, String sharedDataPath, Settings settings) throws IOException {
         Settings build = Settings.builder()
                 .put(settings)
-                .put("path.home", createTempDir().toAbsolutePath().toString())
-                .put("path.shared_data", sharedDataPath)
-                .putArray("path.data", dataPaths).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toAbsolutePath().toString())
+                .put(Environment.PATH_SHARED_DATA_SETTING.getKey(), sharedDataPath)
+                .putArray(Environment.PATH_DATA_SETTING.getKey(), dataPaths).build();
         return new NodeEnvironment(build, new Environment(build));
     }
 }
diff --git a/core/src/test/java/org/elasticsearch/gateway/RecoveryFromGatewayIT.java b/core/src/test/java/org/elasticsearch/gateway/RecoveryFromGatewayIT.java
index e93d8fbcf4..e2cb4bc792 100644
--- a/core/src/test/java/org/elasticsearch/gateway/RecoveryFromGatewayIT.java
+++ b/core/src/test/java/org/elasticsearch/gateway/RecoveryFromGatewayIT.java
@@ -28,6 +28,7 @@ import org.elasticsearch.cluster.routing.allocation.decider.EnableAllocationDeci
 import org.elasticsearch.cluster.routing.allocation.decider.ThrottlingAllocationDecider;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentFactory;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.engine.Engine;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.indices.recovery.RecoveryState;
@@ -438,11 +439,11 @@ public class RecoveryFromGatewayIT extends ESIntegTestCase {
     public void testRecoveryDifferentNodeOrderStartup() throws Exception {
         // we need different data paths so we make sure we start the second node fresh
 
-        final String node_1 = internalCluster().startNode(settingsBuilder().put("path.data", createTempDir()).build());
+        final String node_1 = internalCluster().startNode(settingsBuilder().put(Environment.PATH_DATA_SETTING.getKey(), createTempDir()).build());
 
         client().prepareIndex("test", "type1", "1").setSource("field", "value").execute().actionGet();
 
-        internalCluster().startNode(settingsBuilder().put("path.data", createTempDir()).build());
+        internalCluster().startNode(settingsBuilder().put(Environment.PATH_DATA_SETTING.getKey(), createTempDir()).build());
 
         ensureGreen();
 
diff --git a/core/src/test/java/org/elasticsearch/index/IndexModuleTests.java b/core/src/test/java/org/elasticsearch/index/IndexModuleTests.java
index eae3e65c40..2665629649 100644
--- a/core/src/test/java/org/elasticsearch/index/IndexModuleTests.java
+++ b/core/src/test/java/org/elasticsearch/index/IndexModuleTests.java
@@ -117,7 +117,7 @@ public class IndexModuleTests extends ESTestCase {
     public void setUp() throws Exception {
         super.setUp();
         index = new Index("foo");
-        settings = Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).put("path.home", createTempDir().toString()).build();
+        settings = Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
         indexSettings = IndexSettingsModule.newIndexSettings(index, settings);
         environment = new Environment(settings);
         nodeServicesProvider = newNodeServiceProvider(settings, environment, null);
@@ -148,7 +148,12 @@ public class IndexModuleTests extends ESTestCase {
 
     public void testRegisterIndexStore() throws IOException {
         final Index index = new Index("foo");
-        final Settings settings = Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).put("path.home", createTempDir().toString()).put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), "foo_store").build();
+        final Settings settings = Settings
+            .builder()
+            .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+            .put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), "foo_store")
+            .build();
         IndexSettings indexSettings = IndexSettingsModule.newIndexSettings(index, settings);
         IndexModule module = new IndexModule(indexSettings, null, new AnalysisRegistry(null, environment));
         module.addIndexStore("foo_store", FooStore::new);
@@ -210,7 +215,7 @@ public class IndexModuleTests extends ESTestCase {
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .put("index.similarity.my_similarity.type", "test_similarity")
                 .put("index.similarity.my_similarity.key", "there is a key")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
         module.addSimilarity("test_similarity", (string, settings) -> new SimilarityProvider() {
@@ -238,7 +243,7 @@ public class IndexModuleTests extends ESTestCase {
         Settings indexSettings = Settings.settingsBuilder()
                 .put("index.similarity.my_similarity.type", "test_similarity")
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
         try {
@@ -251,7 +256,7 @@ public class IndexModuleTests extends ESTestCase {
     public void testSetupWithoutType() throws IOException {
         Settings indexSettings = Settings.settingsBuilder()
                 .put("index.similarity.my_similarity.foo", "bar")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
@@ -264,7 +269,7 @@ public class IndexModuleTests extends ESTestCase {
 
     public void testCannotRegisterProvidedImplementations() {
         Settings indexSettings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
         try {
@@ -292,7 +297,7 @@ public class IndexModuleTests extends ESTestCase {
     public void testRegisterCustomQueryCache() throws IOException {
         Settings indexSettings = Settings.settingsBuilder()
                 .put(IndexModule.INDEX_QUERY_CACHE_TYPE_SETTING.getKey(), "custom")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
         module.registerQueryCache("custom", (a, b) -> new CustomQueryCache());
@@ -310,7 +315,7 @@ public class IndexModuleTests extends ESTestCase {
 
     public void testDefaultQueryCacheImplIsSelected() throws IOException {
         Settings indexSettings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).build();
         IndexModule module = new IndexModule(IndexSettingsModule.newIndexSettings(new Index("foo"), indexSettings), null, new AnalysisRegistry(null, environment));
         IndexService indexService = module.newIndexService(nodeEnvironment, deleter, nodeServicesProvider, mapperRegistry);
diff --git a/core/src/test/java/org/elasticsearch/index/IndexWithShadowReplicasIT.java b/core/src/test/java/org/elasticsearch/index/IndexWithShadowReplicasIT.java
index 7012ebbc5a..5d54f7731c 100644
--- a/core/src/test/java/org/elasticsearch/index/IndexWithShadowReplicasIT.java
+++ b/core/src/test/java/org/elasticsearch/index/IndexWithShadowReplicasIT.java
@@ -36,6 +36,7 @@ import org.elasticsearch.cluster.routing.RoutingNodes;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.unit.ByteSizeUnit;
 import org.elasticsearch.common.unit.ByteSizeValue;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.shard.IndexShard;
 import org.elasticsearch.index.shard.ShadowIndexShard;
 import org.elasticsearch.index.translog.TranslogStats;
@@ -86,7 +87,7 @@ public class IndexWithShadowReplicasIT extends ESIntegTestCase {
     private Settings nodeSettings(String dataPath) {
         return Settings.builder()
                 .put("node.add_id_to_custom_path", false)
-                .put("path.shared_data", dataPath)
+                .put(Environment.PATH_SHARED_DATA_SETTING.getKey(), dataPath)
                 .put("index.store.fs.fs_lock", randomFrom("native", "simple"))
                 .build();
     }
@@ -443,7 +444,7 @@ public class IndexWithShadowReplicasIT extends ESIntegTestCase {
         Path dataPath = createTempDir();
         Settings nodeSettings = Settings.builder()
                 .put("node.add_id_to_custom_path", false)
-                .put("path.shared_data", dataPath)
+                .put(Environment.PATH_SHARED_DATA_SETTING.getKey(), dataPath)
                 .build();
 
         String node1 = internalCluster().startNode(nodeSettings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/ASCIIFoldingTokenFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/ASCIIFoldingTokenFilterFactoryTests.java
index 17bd9d587b..ba3f8b2e10 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/ASCIIFoldingTokenFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/ASCIIFoldingTokenFilterFactoryTests.java
@@ -21,6 +21,7 @@ package org.elasticsearch.index.analysis;
 
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.WhitespaceTokenizer;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -31,7 +32,7 @@ import static org.elasticsearch.common.settings.Settings.settingsBuilder;
 public class ASCIIFoldingTokenFilterFactoryTests extends ESTokenStreamTestCase {
     public void testDefault() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_ascii_folding.type", "asciifolding")
                 .build());
         TokenFilterFactory tokenFilter = analysisService.tokenFilter("my_ascii_folding");
@@ -44,7 +45,7 @@ public class ASCIIFoldingTokenFilterFactoryTests extends ESTokenStreamTestCase {
 
     public void testPreserveOriginal() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_ascii_folding.type", "asciifolding")
                 .put("index.analysis.filter.my_ascii_folding.preserve_original", true)
                 .build());
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisModuleTests.java b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisModuleTests.java
index f844d9ac7a..5da5415848 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisModuleTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisModuleTests.java
@@ -81,7 +81,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
     private Settings loadFromClasspath(String path) {
         return settingsBuilder().loadFromStream(path, getClass().getResourceAsStream(path))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
 
     }
@@ -106,7 +106,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
         String yaml = "/org/elasticsearch/index/analysis/test1.yml";
         Settings settings2 = settingsBuilder()
                 .loadFromStream(yaml, getClass().getResourceAsStream(yaml))
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.V_0_90_0)
                 .build();
         AnalysisRegistry newRegistry = getNewRegistry(settings2);
@@ -130,7 +130,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
     private void assertTokenFilter(String name, Class clazz) throws IOException {
         Settings settings = Settings.settingsBuilder()
                                .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                               .put("path.home", createTempDir().toString()).build();
+                               .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
         TokenFilterFactory tokenFilter = analysisService.tokenFilter(name);
         Tokenizer tokenizer = new WhitespaceTokenizer();
@@ -215,7 +215,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
 
     public void testWordListPath() throws Exception {
         Settings settings = Settings.builder()
-                               .put("path.home", createTempDir().toString())
+                               .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                                .build();
         Environment env = new Environment(settings);
         String[] words = new String[]{"donau", "dampf", "schiff", "spargel", "creme", "suppe"};
@@ -243,7 +243,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
     public void testUnderscoreInAnalyzerName() throws IOException {
         Settings settings = Settings.builder()
                 .put("index.analysis.analyzer._invalid_name.tokenizer", "keyword")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, "1")
                 .build();
         try {
@@ -258,7 +258,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
         Settings settings = Settings.builder()
                 .put("index.analysis.analyzer.valid_name.tokenizer", "keyword")
                 .put("index.analysis.analyzer.valid_name.alias", "_invalid_name")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, "1")
                 .build();
         try {
@@ -275,7 +275,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
                 .put("index.analysis.analyzer.custom1.position_offset_gap", "128")
                 .put("index.analysis.analyzer.custom2.tokenizer", "standard")
                 .put("index.analysis.analyzer.custom2.position_increment_gap", "256")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, VersionUtils.randomVersionBetween(random(), Version.V_1_0_0,
                         Version.V_1_7_1))
                 .build();
@@ -295,7 +295,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
                 .put("index.analysis.analyzer.custom.tokenizer", "standard")
                 .put("index.analysis.analyzer.custom.position_offset_gap", "128")
                 .put("index.analysis.analyzer.custom.position_increment_gap", "256")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, VersionUtils.randomVersionBetween(random(), Version.V_1_0_0,
                         Version.V_1_7_1))
                 .build();
@@ -312,7 +312,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
         Settings settings = settingsBuilder()
                 .put("index.analysis.analyzer.custom.tokenizer", "standard")
                 .put("index.analysis.analyzer.custom.position_offset_gap", "128")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
         try {
@@ -326,7 +326,7 @@ public class AnalysisModuleTests extends ModuleTestCase {
 
     public void testRegisterHunspellDictionary() throws Exception {
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
         AnalysisModule module = new AnalysisModule(new Environment(settings));
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisServiceTests.java b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisServiceTests.java
index f467aa289f..3dfb0975ab 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisServiceTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisServiceTests.java
@@ -53,7 +53,11 @@ public class AnalysisServiceTests extends ESTestCase {
 
     public void testDefaultAnalyzers() throws IOException {
         Version version = VersionUtils.randomVersion(getRandom());
-        Settings settings = Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, version).put("path.home", createTempDir().toString()).build();
+        Settings settings = Settings
+            .builder()
+            .put(IndexMetaData.SETTING_VERSION_CREATED, version)
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+            .build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(new Index("index"), settings);
         AnalysisService analysisService = new AnalysisRegistry(null, new Environment(settings)).build(idxSettings);
         assertThat(analysisService.defaultIndexAnalyzer().analyzer(), instanceOf(StandardAnalyzer.class));
@@ -123,7 +127,7 @@ public class AnalysisServiceTests extends ESTestCase {
 
     public void testConfigureCamelCaseTokenFilter() throws IOException {
         // tests a filter that
-        Settings settings = Settings.builder().put("path.home", createTempDir().toString()).build();
+        Settings settings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
         Settings indexSettings = settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .put("index.analysis.filter.wordDelimiter.type", "word_delimiter")
@@ -169,7 +173,7 @@ public class AnalysisServiceTests extends ESTestCase {
     }
 
     public void testCameCaseOverride() throws IOException {
-        Settings settings = Settings.builder().put("path.home", createTempDir().toString()).build();
+        Settings settings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
         Settings indexSettings = settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .put("index.analysis.filter.wordDelimiter.type", "word_delimiter")
@@ -196,7 +200,7 @@ public class AnalysisServiceTests extends ESTestCase {
     }
 
     public void testBuiltInAnalyzersAreCached() throws IOException {
-        Settings settings = Settings.builder().put("path.home", createTempDir().toString()).build();
+        Settings settings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString()).build();
         Settings indexSettings = settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(new Index("index"), indexSettings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisTestsHelper.java b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisTestsHelper.java
index 1404716b0c..7460ddd3e5 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/AnalysisTestsHelper.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/AnalysisTestsHelper.java
@@ -37,7 +37,7 @@ public class AnalysisTestsHelper {
     public static AnalysisService createAnalysisServiceFromClassPath(Path baseDir, String resource) throws IOException {
         Settings settings = Settings.settingsBuilder()
                 .loadFromStream(resource, AnalysisTestsHelper.class.getResourceAsStream(resource))
-                .put("path.home", baseDir.toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), baseDir.toString())
                 .build();
 
         return createAnalysisServiceFromSettings(settings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/AnalyzerBackwardsCompatTests.java b/core/src/test/java/org/elasticsearch/index/analysis/AnalyzerBackwardsCompatTests.java
index 63acbc81c8..a163d9e42b 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/AnalyzerBackwardsCompatTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/AnalyzerBackwardsCompatTests.java
@@ -19,6 +19,7 @@
 package org.elasticsearch.index.analysis;
 
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -41,7 +42,7 @@ public class AnalyzerBackwardsCompatTests extends ESTokenStreamTestCase {
                 builder.put(SETTING_VERSION_CREATED, version);
             }
             builder.put("index.analysis.analyzer.foo.type", type);
-            builder.put("path.home", createTempDir().toString());
+            builder.put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString());
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(builder.build());
             NamedAnalyzer analyzer = analysisService.analyzer("foo");
             assertNotNull(analyzer);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/CharFilterTests.java b/core/src/test/java/org/elasticsearch/index/analysis/CharFilterTests.java
index dd08d47013..c39c6e702f 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/CharFilterTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/CharFilterTests.java
@@ -40,7 +40,7 @@ public class CharFilterTests extends ESTokenStreamTestCase {
                 .putArray("index.analysis.char_filter.my_mapping.mappings", "ph=>f", "qu=>q")
                 .put("index.analysis.analyzer.custom_with_char_filter.tokenizer", "standard")
                 .putArray("index.analysis.analyzer.custom_with_char_filter.char_filter", "my_mapping")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(index, settings);
         AnalysisService analysisService = new AnalysisRegistry(null, new Environment(settings)).build(idxSettings);
@@ -58,7 +58,7 @@ public class CharFilterTests extends ESTokenStreamTestCase {
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .put("index.analysis.analyzer.custom_with_char_filter.tokenizer", "standard")
                 .putArray("index.analysis.analyzer.custom_with_char_filter.char_filter", "html_strip")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(index, settings);
         AnalysisService analysisService = new AnalysisRegistry(null, new Environment(settings)).build(idxSettings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/CompoundAnalysisTests.java b/core/src/test/java/org/elasticsearch/index/analysis/CompoundAnalysisTests.java
index a097d55f4a..e00f5f67d8 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/CompoundAnalysisTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/CompoundAnalysisTests.java
@@ -98,7 +98,7 @@ public class CompoundAnalysisTests extends ESTestCase {
         return settingsBuilder()
                 .loadFromStream(json, getClass().getResourceAsStream(json))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
     }
 
@@ -107,7 +107,7 @@ public class CompoundAnalysisTests extends ESTestCase {
         return settingsBuilder()
                 .loadFromStream(yaml, getClass().getResourceAsStream(yaml))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
     }
 }
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/HunspellTokenFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/HunspellTokenFilterFactoryTests.java
index 02c4e1a264..51d8b9214a 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/HunspellTokenFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/HunspellTokenFilterFactoryTests.java
@@ -19,6 +19,7 @@
 package org.elasticsearch.index.analysis;
 
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 
 import java.io.IOException;
@@ -30,8 +31,8 @@ import static org.hamcrest.Matchers.is;
 public class HunspellTokenFilterFactoryTests extends ESTestCase {
     public void testDedup() throws IOException {
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir().toString())
-                .put("path.conf", getDataPath("/indices/analyze/conf_dir"))
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/conf_dir"))
                 .put("index.analysis.filter.en_US.type", "hunspell")
                 .put("index.analysis.filter.en_US.locale", "en_US")
                 .build();
@@ -43,8 +44,8 @@ public class HunspellTokenFilterFactoryTests extends ESTestCase {
         assertThat(hunspellTokenFilter.dedup(), is(true));
 
         settings = settingsBuilder()
-                .put("path.home", createTempDir().toString())
-                .put("path.conf", getDataPath("/indices/analyze/conf_dir"))
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/conf_dir"))
                 .put("index.analysis.filter.en_US.type", "hunspell")
                 .put("index.analysis.filter.en_US.dedup", false)
                 .put("index.analysis.filter.en_US.locale", "en_US")
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/KeepFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/KeepFilterFactoryTests.java
index 99c936cd34..a7179daff2 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/KeepFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/KeepFilterFactoryTests.java
@@ -22,6 +22,7 @@ package org.elasticsearch.index.analysis;
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.WhitespaceTokenizer;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 import org.junit.Assert;
 
@@ -41,7 +42,7 @@ public class KeepFilterFactoryTests extends ESTokenStreamTestCase {
 
     public void testLoadOverConfiguredSettings() {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.broken_keep_filter.type", "keep")
                 .put("index.analysis.filter.broken_keep_filter.keep_words_path", "does/not/exists.txt")
                 .put("index.analysis.filter.broken_keep_filter.keep_words", "[\"Hello\", \"worlD\"]")
@@ -57,7 +58,7 @@ public class KeepFilterFactoryTests extends ESTokenStreamTestCase {
 
     public void testKeepWordsPathSettings() {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.non_broken_keep_filter.type", "keep")
                 .put("index.analysis.filter.non_broken_keep_filter.keep_words_path", "does/not/exists.txt")
                 .build();
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/KeepTypesFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/KeepTypesFilterFactoryTests.java
index 1e8a0ba16e..9111c929f9 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/KeepTypesFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/KeepTypesFilterFactoryTests.java
@@ -22,6 +22,7 @@ package org.elasticsearch.index.analysis;
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.standard.StandardTokenizer;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -32,7 +33,7 @@ import static org.hamcrest.Matchers.instanceOf;
 public class KeepTypesFilterFactoryTests extends ESTokenStreamTestCase {
     public void testKeepTypes() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.keep_numbers.type", "keep_types")
                 .putArray("index.analysis.filter.keep_numbers.types", new String[] {"<NUM>", "<SOMETHINGELSE>"})
                 .build();
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/LimitTokenCountFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/LimitTokenCountFilterFactoryTests.java
index e133ffc79a..b266be9f2b 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/LimitTokenCountFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/LimitTokenCountFilterFactoryTests.java
@@ -22,6 +22,7 @@ package org.elasticsearch.index.analysis;
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.WhitespaceTokenizer;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -31,7 +32,7 @@ public class LimitTokenCountFilterFactoryTests extends ESTokenStreamTestCase {
     public void testDefault() throws IOException {
         Settings settings = Settings.settingsBuilder()
                 .put("index.analysis.filter.limit_default.type", "limit")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
         {
@@ -58,7 +59,7 @@ public class LimitTokenCountFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.filter.limit_1.type", "limit")
                     .put("index.analysis.filter.limit_1.max_token_count", 3)
                     .put("index.analysis.filter.limit_1.consume_all_tokens", true)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("limit_1");
@@ -73,7 +74,7 @@ public class LimitTokenCountFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.filter.limit_1.type", "limit")
                     .put("index.analysis.filter.limit_1.max_token_count", 3)
                     .put("index.analysis.filter.limit_1.consume_all_tokens", false)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("limit_1");
@@ -89,7 +90,7 @@ public class LimitTokenCountFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.filter.limit_1.type", "limit")
                     .put("index.analysis.filter.limit_1.max_token_count", 17)
                     .put("index.analysis.filter.limit_1.consume_all_tokens", true)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("limit_1");
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/PatternCaptureTokenFilterTests.java b/core/src/test/java/org/elasticsearch/index/analysis/PatternCaptureTokenFilterTests.java
index 4b7119df01..8c6775a92a 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/PatternCaptureTokenFilterTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/PatternCaptureTokenFilterTests.java
@@ -35,7 +35,7 @@ public class PatternCaptureTokenFilterTests extends ESTokenStreamTestCase {
     public void testPatternCaptureTokenFilter() throws Exception {
         String json = "/org/elasticsearch/index/analysis/pattern_capture.json";
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .loadFromStream(json, getClass().getResourceAsStream(json))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/StemmerTokenFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/StemmerTokenFilterFactoryTests.java
index 737a991f0e..37844dce69 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/StemmerTokenFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/StemmerTokenFilterFactoryTests.java
@@ -25,6 +25,7 @@ import org.apache.lucene.analysis.en.PorterStemFilter;
 import org.apache.lucene.analysis.snowball.SnowballFilter;
 import org.elasticsearch.Version;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 import org.elasticsearch.test.VersionUtils;
 
@@ -50,7 +51,7 @@ public class StemmerTokenFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.analyzer.my_english.tokenizer","whitespace")
                     .put("index.analysis.analyzer.my_english.filter","my_english")
                     .put(SETTING_VERSION_CREATED,v)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
 
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -83,7 +84,7 @@ public class StemmerTokenFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.analyzer.my_porter2.tokenizer","whitespace")
                     .put("index.analysis.analyzer.my_porter2.filter","my_porter2")
                     .put(SETTING_VERSION_CREATED,v)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
 
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/StopAnalyzerTests.java b/core/src/test/java/org/elasticsearch/index/analysis/StopAnalyzerTests.java
index 90e55e98d7..ebaf4cb5cc 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/StopAnalyzerTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/StopAnalyzerTests.java
@@ -35,7 +35,7 @@ public class StopAnalyzerTests extends ESTokenStreamTestCase {
         String json = "/org/elasticsearch/index/analysis/stop.json";
         Settings settings = settingsBuilder()
             .loadFromStream(json, getClass().getResourceAsStream(json))
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(new Index("index"), settings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/StopTokenFilterTests.java b/core/src/test/java/org/elasticsearch/index/analysis/StopTokenFilterTests.java
index 1dbd9ac2bd..2804f522af 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/StopTokenFilterTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/StopTokenFilterTests.java
@@ -28,6 +28,7 @@ import org.apache.lucene.search.suggest.analyzing.SuggestStopFilter;
 import org.apache.lucene.util.Version;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.Settings.Builder;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -44,7 +45,7 @@ public class StopTokenFilterTests extends ESTokenStreamTestCase {
         if (random().nextBoolean()) {
             builder.put("index.analysis.filter.my_stop.version", "5.0");
         }
-        builder.put("path.home", createTempDir().toString());
+        builder.put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString());
         Settings settings = builder.build();
         try {
             AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -67,7 +68,7 @@ public class StopTokenFilterTests extends ESTokenStreamTestCase {
         } else {
             // don't specify
         }
-        builder.put("path.home", createTempDir().toString());
+        builder.put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString());
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(builder.build());
         TokenFilterFactory tokenFilter = analysisService.tokenFilter("my_stop");
         assertThat(tokenFilter, instanceOf(StopTokenFilterFactory.class));
@@ -86,7 +87,7 @@ public class StopTokenFilterTests extends ESTokenStreamTestCase {
                 .put("index.analysis.filter.my_stop.type", "stop")
                 .put("index.analysis.filter.my_stop.enable_position_increments", false)
                 .put("index.analysis.filter.my_stop.version", "4.3")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
         TokenFilterFactory tokenFilter = analysisService.tokenFilter("my_stop");
@@ -101,7 +102,7 @@ public class StopTokenFilterTests extends ESTokenStreamTestCase {
         Settings settings = Settings.settingsBuilder()
                 .put("index.analysis.filter.my_stop.type", "stop")
                 .put("index.analysis.filter.my_stop.remove_trailing", false)
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
         TokenFilterFactory tokenFilter = analysisService.tokenFilter("my_stop");
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/WordDelimiterTokenFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/WordDelimiterTokenFilterFactoryTests.java
index 54810028ae..a041694dde 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/WordDelimiterTokenFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/WordDelimiterTokenFilterFactoryTests.java
@@ -21,6 +21,7 @@ package org.elasticsearch.index.analysis;
 
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.WhitespaceTokenizer;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTokenStreamTestCase;
 
 import java.io.IOException;
@@ -31,7 +32,7 @@ import static org.elasticsearch.common.settings.Settings.settingsBuilder;
 public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase {
     public void testDefault() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .build());
         TokenFilterFactory tokenFilter = analysisService.tokenFilter("my_word_delimiter");
@@ -44,7 +45,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testCatenateWords() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.catenate_words", "true")
                 .put("index.analysis.filter.my_word_delimiter.generate_word_parts", "false")
@@ -59,7 +60,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testCatenateNumbers() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.generate_number_parts", "false")
                 .put("index.analysis.filter.my_word_delimiter.catenate_numbers", "true")
@@ -74,7 +75,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testCatenateAll() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.generate_word_parts", "false")
                 .put("index.analysis.filter.my_word_delimiter.generate_number_parts", "false")
@@ -90,7 +91,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testSplitOnCaseChange() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.split_on_case_change", "false")
                 .build());
@@ -104,7 +105,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testPreserveOriginal() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.preserve_original", "true")
                 .build());
@@ -118,7 +119,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
 
     public void testStemEnglishPossessive() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.stem_english_possessive", "false")
                 .build());
@@ -133,7 +134,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
     /** Correct offset order when doing both parts and concatenation: PowerShot is a synonym of Power */
     public void testPartsAndCatenate() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.catenate_words", "true")
                 .put("index.analysis.filter.my_word_delimiter.generate_word_parts", "true")
@@ -150,7 +151,7 @@ public class WordDelimiterTokenFilterFactoryTests extends ESTokenStreamTestCase
      * old offset order when doing both parts and concatenation: PowerShot is a synonym of Shot */
     public void testDeprecatedPartsAndCatenate() throws IOException {
         AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settingsBuilder()
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .put("index.analysis.filter.my_word_delimiter.type", "word_delimiter")
                 .put("index.analysis.filter.my_word_delimiter.catenate_words", "true")
                 .put("index.analysis.filter.my_word_delimiter.generate_word_parts", "true")
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/commongrams/CommonGramsTokenFilterFactoryTests.java b/core/src/test/java/org/elasticsearch/index/analysis/commongrams/CommonGramsTokenFilterFactoryTests.java
index f7c346c657..a9d3c8820f 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/commongrams/CommonGramsTokenFilterFactoryTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/commongrams/CommonGramsTokenFilterFactoryTests.java
@@ -23,6 +23,7 @@ import org.apache.lucene.analysis.Analyzer;
 import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.WhitespaceTokenizer;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.analysis.AnalysisService;
 import org.elasticsearch.index.analysis.AnalysisTestsHelper;
 import org.elasticsearch.index.analysis.TokenFilterFactory;
@@ -38,7 +39,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
     public void testDefault() throws IOException {
         Settings settings = Settings.settingsBuilder()
                                 .put("index.analysis.filter.common_grams_default.type", "common_grams")
-                                .put("path.home", createTempDir().toString())
+                                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                                 .build();
 
         try {
@@ -54,7 +55,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_default.type", "common_grams")
                      .putArray("index.analysis.filter.common_grams_default.common_words", "chromosome", "protein")
-                     .put("path.home", createTempDir().toString())
+                     .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                      .build();
 
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -71,7 +72,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_default.type", "common_grams")
                      .put("index.analysis.filter.common_grams_default.query_mode", false)
-                     .put("path.home", createTempDir().toString())
+                     .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                      .putArray("index.analysis.filter.common_grams_default.common_words", "chromosome", "protein")
                      .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -90,7 +91,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_1.type", "common_grams")
                     .put("index.analysis.filter.common_grams_1.ignore_case", true)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .putArray("index.analysis.filter.common_grams_1.common_words", "the", "Or", "Not", "a", "is", "an", "they", "are")
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -104,7 +105,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_2.type", "common_grams")
                     .put("index.analysis.filter.common_grams_2.ignore_case", false)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .putArray("index.analysis.filter.common_grams_2.common_words", "the", "Or", "noT", "a", "is", "an", "they", "are")
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -118,7 +119,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_3.type", "common_grams")
                     .putArray("index.analysis.filter.common_grams_3.common_words", "the", "or", "not", "a", "is", "an", "they", "are")
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("common_grams_3");
@@ -134,7 +135,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         String json = "/org/elasticsearch/index/analysis/commongrams/commongrams.json";
         Settings settings = Settings.settingsBuilder()
                      .loadFromStream(json, getClass().getResourceAsStream(json))
-                     .put("path.home", createHome())
+                     .put(Environment.PATH_HOME_SETTING.getKey(), createHome())
                      .build();
         {
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
@@ -158,7 +159,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.filter.common_grams_1.query_mode", true)
                     .putArray("index.analysis.filter.common_grams_1.common_words", "the", "Or", "Not", "a", "is", "an", "they", "are")
                     .put("index.analysis.filter.common_grams_1.ignore_case", true)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("common_grams_1");
@@ -173,7 +174,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
                     .put("index.analysis.filter.common_grams_2.query_mode", true)
                     .putArray("index.analysis.filter.common_grams_2.common_words", "the", "Or", "noT", "a", "is", "an", "they", "are")
                     .put("index.analysis.filter.common_grams_2.ignore_case", false)
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("common_grams_2");
@@ -187,7 +188,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_3.type", "common_grams")
                     .put("index.analysis.filter.common_grams_3.query_mode", true)
                     .putArray("index.analysis.filter.common_grams_3.common_words", "the", "Or", "noT", "a", "is", "an", "they", "are")
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("common_grams_3");
@@ -201,7 +202,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
             Settings settings = Settings.settingsBuilder().put("index.analysis.filter.common_grams_4.type", "common_grams")
                     .put("index.analysis.filter.common_grams_4.query_mode", true)
                     .putArray("index.analysis.filter.common_grams_4.common_words", "the", "or", "not", "a", "is", "an", "they", "are")
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
             TokenFilterFactory tokenFilter = analysisService.tokenFilter("common_grams_4");
@@ -217,7 +218,7 @@ public class CommonGramsTokenFilterFactoryTests extends ESTokenStreamTestCase {
         String json = "/org/elasticsearch/index/analysis/commongrams/commongrams_query_mode.json";
         Settings settings = Settings.settingsBuilder()
                 .loadFromStream(json, getClass().getResourceAsStream(json))
-            .put("path.home", createHome())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createHome())
                 .build();
         {
             AnalysisService analysisService = AnalysisTestsHelper.createAnalysisServiceFromSettings(settings);
diff --git a/core/src/test/java/org/elasticsearch/index/analysis/synonyms/SynonymsAnalysisTests.java b/core/src/test/java/org/elasticsearch/index/analysis/synonyms/SynonymsAnalysisTests.java
index 3a6adca1c6..c4c664f222 100644
--- a/core/src/test/java/org/elasticsearch/index/analysis/synonyms/SynonymsAnalysisTests.java
+++ b/core/src/test/java/org/elasticsearch/index/analysis/synonyms/SynonymsAnalysisTests.java
@@ -64,7 +64,7 @@ public class SynonymsAnalysisTests extends ESTestCase {
         String json = "/org/elasticsearch/index/analysis/synonyms/synonyms.json";
         Settings settings = settingsBuilder().
             loadFromStream(json, getClass().getResourceAsStream(json))
-                .put("path.home", home)
+                .put(Environment.PATH_HOME_SETTING.getKey(), home)
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT).build();
 
         IndexSettings idxSettings = IndexSettingsModule.newIndexSettings(new Index("index"), settings);
diff --git a/core/src/test/java/org/elasticsearch/index/codec/CodecTests.java b/core/src/test/java/org/elasticsearch/index/codec/CodecTests.java
index 7cfe52d1c0..c293237b5a 100644
--- a/core/src/test/java/org/elasticsearch/index/codec/CodecTests.java
+++ b/core/src/test/java/org/elasticsearch/index/codec/CodecTests.java
@@ -106,7 +106,7 @@ public class CodecTests extends ESTestCase {
 
     private static CodecService createCodecService() throws IOException {
         Settings nodeSettings = settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .build();
         IndexSettings settings = IndexSettingsModule.newIndexSettings(new Index("_na"), nodeSettings);
         SimilarityService similarityService = new SimilarityService(settings, Collections.emptyMap());
diff --git a/core/src/test/java/org/elasticsearch/index/query/AbstractQueryTestCase.java b/core/src/test/java/org/elasticsearch/index/query/AbstractQueryTestCase.java
index 52aa7ea48f..8c6bfff3fa 100644
--- a/core/src/test/java/org/elasticsearch/index/query/AbstractQueryTestCase.java
+++ b/core/src/test/java/org/elasticsearch/index/query/AbstractQueryTestCase.java
@@ -186,7 +186,7 @@ public abstract class AbstractQueryTestCase<QB extends AbstractQueryBuilder<QB>>
         Version version = randomBoolean() ? Version.CURRENT : VersionUtils.randomVersionBetween(random(), Version.V_2_0_0_beta1, Version.CURRENT);
         Settings settings = Settings.settingsBuilder()
                 .put("name", AbstractQueryTestCase.class.toString())
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put(ScriptService.SCRIPT_AUTO_RELOAD_ENABLED_SETTING, false)
                 .build();
         Settings indexSettings = Settings.settingsBuilder()
@@ -218,7 +218,7 @@ public abstract class AbstractQueryTestCase<QB extends AbstractQueryBuilder<QB>>
                     @Override
                     protected void configure() {
                         Settings settings = Settings.builder()
-                                .put("path.home", createTempDir())
+                                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                                 // no file watching, so we don't need a ResourceWatcherService
                                 .put(ScriptService.SCRIPT_AUTO_RELOAD_ENABLED_SETTING, false)
                                 .build();
diff --git a/core/src/test/java/org/elasticsearch/index/shard/NewPathForShardTests.java b/core/src/test/java/org/elasticsearch/index/shard/NewPathForShardTests.java
index c3a2d65748..911f2598f0 100644
--- a/core/src/test/java/org/elasticsearch/index/shard/NewPathForShardTests.java
+++ b/core/src/test/java/org/elasticsearch/index/shard/NewPathForShardTests.java
@@ -167,8 +167,8 @@ public class NewPathForShardTests extends ESTestCase {
                                        path.resolve("b").toString()};
 
         Settings settings = Settings.builder()
-            .put("path.home", path)
-            .putArray("path.data", paths).build();
+            .put(Environment.PATH_HOME_SETTING.getKey(), path)
+            .putArray(Environment.PATH_DATA_SETTING.getKey(), paths).build();
         NodeEnvironment nodeEnv = new NodeEnvironment(settings, new Environment(settings));
 
         // Make sure all our mocking above actually worked:
diff --git a/core/src/test/java/org/elasticsearch/index/shard/ShardPathTests.java b/core/src/test/java/org/elasticsearch/index/shard/ShardPathTests.java
index 5a82a8942a..80d5f4c8fe 100644
--- a/core/src/test/java/org/elasticsearch/index/shard/ShardPathTests.java
+++ b/core/src/test/java/org/elasticsearch/index/shard/ShardPathTests.java
@@ -22,6 +22,7 @@ import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.cluster.routing.AllocationId;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.IndexSettingsModule;
@@ -118,7 +119,7 @@ public class ShardPathTests extends ESTestCase {
             final Path path = createTempDir();
             final boolean includeNodeId = randomBoolean();
             indexSetttings = indexSettingsBuilder.put(IndexMetaData.SETTING_DATA_PATH, "custom").build();
-            nodeSettings = settingsBuilder().put("path.shared_data", path.toAbsolutePath().toAbsolutePath())
+            nodeSettings = settingsBuilder().put(Environment.PATH_SHARED_DATA_SETTING.getKey(), path.toAbsolutePath().toAbsolutePath())
                     .put(NodeEnvironment.ADD_NODE_ID_TO_CUSTOM_PATH, includeNodeId).build();
             if (includeNodeId) {
                 customPath = path.resolve("custom").resolve("0");
diff --git a/core/src/test/java/org/elasticsearch/indices/analyze/HunspellServiceIT.java b/core/src/test/java/org/elasticsearch/indices/analyze/HunspellServiceIT.java
index 722a4ebde8..a8c1a6a019 100644
--- a/core/src/test/java/org/elasticsearch/indices/analyze/HunspellServiceIT.java
+++ b/core/src/test/java/org/elasticsearch/indices/analyze/HunspellServiceIT.java
@@ -22,6 +22,7 @@ import org.apache.lucene.analysis.hunspell.Dictionary;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.ExceptionsHelper;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.indices.analysis.HunspellService;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESIntegTestCase.ClusterScope;
@@ -39,7 +40,7 @@ import static org.hamcrest.Matchers.notNullValue;
 public class HunspellServiceIT extends ESIntegTestCase {
     public void testLocaleDirectoryWithNodeLevelConfig() throws Exception {
         Settings settings = Settings.settingsBuilder()
-                .put("path.conf", getDataPath("/indices/analyze/conf_dir"))
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/conf_dir"))
                 .put(HUNSPELL_LAZY_LOAD, randomBoolean())
                 .put(HUNSPELL_IGNORE_CASE, true)
                 .build();
@@ -52,7 +53,7 @@ public class HunspellServiceIT extends ESIntegTestCase {
 
     public void testLocaleDirectoryWithLocaleSpecificConfig() throws Exception {
         Settings settings = Settings.settingsBuilder()
-                .put("path.conf", getDataPath("/indices/analyze/conf_dir"))
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/conf_dir"))
                 .put(HUNSPELL_LAZY_LOAD, randomBoolean())
                 .put(HUNSPELL_IGNORE_CASE, true)
                 .put("indices.analysis.hunspell.dictionary.en_US.strict_affix_parsing", false)
@@ -74,7 +75,7 @@ public class HunspellServiceIT extends ESIntegTestCase {
 
     public void testDicWithNoAff() throws Exception {
         Settings settings = Settings.settingsBuilder()
-                .put("path.conf", getDataPath("/indices/analyze/no_aff_conf_dir"))
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/no_aff_conf_dir"))
                 .put(HUNSPELL_LAZY_LOAD, randomBoolean())
                 .build();
 
@@ -92,7 +93,7 @@ public class HunspellServiceIT extends ESIntegTestCase {
 
     public void testDicWithTwoAffs() throws Exception {
         Settings settings = Settings.settingsBuilder()
-                .put("path.conf", getDataPath("/indices/analyze/two_aff_conf_dir"))
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/indices/analyze/two_aff_conf_dir"))
                 .put(HUNSPELL_LAZY_LOAD, randomBoolean())
                 .build();
 
diff --git a/core/src/test/java/org/elasticsearch/indices/store/IndicesStoreIntegrationIT.java b/core/src/test/java/org/elasticsearch/indices/store/IndicesStoreIntegrationIT.java
index 18d56eee88..9826a78789 100644
--- a/core/src/test/java/org/elasticsearch/indices/store/IndicesStoreIntegrationIT.java
+++ b/core/src/test/java/org/elasticsearch/indices/store/IndicesStoreIntegrationIT.java
@@ -41,6 +41,7 @@ import org.elasticsearch.common.Priority;
 import org.elasticsearch.common.logging.ESLogger;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.unit.TimeValue;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.index.Index;
 import org.elasticsearch.index.shard.ShardId;
@@ -82,7 +83,7 @@ import static org.hamcrest.Matchers.equalTo;
 public class IndicesStoreIntegrationIT extends ESIntegTestCase {
     @Override
     protected Settings nodeSettings(int nodeOrdinal) { // simplify this and only use a single data path
-        return Settings.settingsBuilder().put(super.nodeSettings(nodeOrdinal)).put("path.data", "")
+        return Settings.settingsBuilder().put(super.nodeSettings(nodeOrdinal)).put(Environment.PATH_DATA_SETTING.getKey(), "")
                 // by default this value is 1 sec in tests (30 sec in practice) but we adding disruption here
                 // which is between 1 and 2 sec can cause each of the shard deletion requests to timeout.
                 // to prevent this we are setting the timeout here to something highish ie. the default in practice
diff --git a/core/src/test/java/org/elasticsearch/node/internal/InternalSettingsPreparerTests.java b/core/src/test/java/org/elasticsearch/node/internal/InternalSettingsPreparerTests.java
index 4dda068ddd..442b1afa6e 100644
--- a/core/src/test/java/org/elasticsearch/node/internal/InternalSettingsPreparerTests.java
+++ b/core/src/test/java/org/elasticsearch/node/internal/InternalSettingsPreparerTests.java
@@ -48,7 +48,7 @@ public class InternalSettingsPreparerTests extends ESTestCase {
     @Before
     public void createBaseEnvSettings() {
         baseEnvSettings = settingsBuilder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .build();
     }
 
@@ -68,7 +68,7 @@ public class InternalSettingsPreparerTests extends ESTestCase {
         assertNotNull(settings.get("name")); // a name was set
         assertNotNull(settings.get(ClusterName.SETTING)); // a cluster name was set
         assertEquals(settings.toString(), size + 1 /* path.home is in the base settings */, settings.names().size());
-        String home = baseEnvSettings.get("path.home");
+        String home = Environment.PATH_HOME_SETTING.get(baseEnvSettings);
         String configDir = env.configFile().toString();
         assertTrue(configDir, configDir.startsWith(home));
     }
diff --git a/core/src/test/java/org/elasticsearch/percolator/PercolatorBackwardsCompatibilityIT.java b/core/src/test/java/org/elasticsearch/percolator/PercolatorBackwardsCompatibilityIT.java
index cb8ffb8e91..9378eaa754 100644
--- a/core/src/test/java/org/elasticsearch/percolator/PercolatorBackwardsCompatibilityIT.java
+++ b/core/src/test/java/org/elasticsearch/percolator/PercolatorBackwardsCompatibilityIT.java
@@ -28,6 +28,7 @@ import org.elasticsearch.cluster.ClusterState;
 import org.elasticsearch.cluster.metadata.MappingMetaData;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.support.XContentMapValues;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.search.sort.SortOrder;
 import org.elasticsearch.test.ESIntegTestCase;
 
@@ -113,7 +114,7 @@ public class PercolatorBackwardsCompatibilityIT extends ESIntegTestCase {
         }
 
         Settings.Builder nodeSettings = Settings.builder()
-            .put("path.data", dataDir);
+            .put(Environment.PATH_DATA_SETTING.getKey(), dataDir);
         internalCluster().startNode(nodeSettings.build());
         ensureGreen(INDEX_NAME);
     }
diff --git a/core/src/test/java/org/elasticsearch/plugins/PluginsServiceTests.java b/core/src/test/java/org/elasticsearch/plugins/PluginsServiceTests.java
index 5d8605ab19..d3c1f1b8ba 100644
--- a/core/src/test/java/org/elasticsearch/plugins/PluginsServiceTests.java
+++ b/core/src/test/java/org/elasticsearch/plugins/PluginsServiceTests.java
@@ -88,7 +88,7 @@ public class PluginsServiceTests extends ESTestCase {
 
     public void testAdditionalSettings() {
         Settings settings = Settings.builder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .put("my.setting", "test")
             .put(IndexModule.INDEX_STORE_TYPE_SETTING.getKey(), IndexModule.Type.SIMPLEFS.getSettingsKey()).build();
         PluginsService service = newPluginsService(settings, AdditionalSettingsPlugin1.class);
@@ -100,7 +100,7 @@ public class PluginsServiceTests extends ESTestCase {
 
     public void testAdditionalSettingsClash() {
         Settings settings = Settings.builder()
-            .put("path.home", createTempDir()).build();
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         PluginsService service = newPluginsService(settings, AdditionalSettingsPlugin1.class, AdditionalSettingsPlugin2.class);
         try {
             service.updatedSettings();
@@ -115,7 +115,7 @@ public class PluginsServiceTests extends ESTestCase {
 
     public void testOnModuleExceptionsArePropagated() {
         Settings settings = Settings.builder()
-                .put("path.home", createTempDir()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         PluginsService service = newPluginsService(settings, FailOnModule.class);
         try {
             service.processModule(new BrokenModule());
diff --git a/core/src/test/java/org/elasticsearch/script/FileScriptTests.java b/core/src/test/java/org/elasticsearch/script/FileScriptTests.java
index 987aef90bc..8ef7bcc41f 100644
--- a/core/src/test/java/org/elasticsearch/script/FileScriptTests.java
+++ b/core/src/test/java/org/elasticsearch/script/FileScriptTests.java
@@ -39,7 +39,7 @@ public class FileScriptTests extends ESTestCase {
         Path mockscript = scriptsDir.resolve("script1.mockscript");
         Files.write(mockscript, "1".getBytes("UTF-8"));
         settings = Settings.builder()
-            .put("path.home", homeDir)
+            .put(Environment.PATH_HOME_SETTING.getKey(), homeDir)
                 // no file watching, so we don't need a ResourceWatcherService
             .put(ScriptService.SCRIPT_AUTO_RELOAD_ENABLED_SETTING, false)
             .put(settings)
diff --git a/core/src/test/java/org/elasticsearch/script/NativeScriptTests.java b/core/src/test/java/org/elasticsearch/script/NativeScriptTests.java
index 47adeabe02..0e8d477d0e 100644
--- a/core/src/test/java/org/elasticsearch/script/NativeScriptTests.java
+++ b/core/src/test/java/org/elasticsearch/script/NativeScriptTests.java
@@ -50,7 +50,7 @@ public class NativeScriptTests extends ESTestCase {
         ContextAndHeaderHolder contextAndHeaders = new ContextAndHeaderHolder();
         Settings settings = Settings.settingsBuilder()
                 .put("name", "testNativeScript")
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .build();
         ScriptModule scriptModule = new ScriptModule(settings);
         scriptModule.registerScript("my", MyNativeScriptFactory.class);
@@ -78,7 +78,7 @@ public class NativeScriptTests extends ESTestCase {
             String scriptContext = randomFrom(ScriptContext.Standard.values()).getKey();
             builder.put(ScriptModes.SCRIPT_SETTINGS_PREFIX + scriptContext, randomFrom(ScriptMode.values()));
         }
-        Settings settings = builder.put("path.home", createTempDir()).build();
+        Settings settings = builder.put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         Environment environment = new Environment(settings);
         ResourceWatcherService resourceWatcherService = new ResourceWatcherService(settings, null);
         Map<String, NativeScriptFactory> nativeScriptFactoryMap = new HashMap<>();
diff --git a/core/src/test/java/org/elasticsearch/script/ScriptContextTests.java b/core/src/test/java/org/elasticsearch/script/ScriptContextTests.java
index 019eb7c74a..36865f254b 100644
--- a/core/src/test/java/org/elasticsearch/script/ScriptContextTests.java
+++ b/core/src/test/java/org/elasticsearch/script/ScriptContextTests.java
@@ -38,7 +38,7 @@ public class ScriptContextTests extends ESTestCase {
 
     ScriptService makeScriptService() throws Exception {
         Settings settings = Settings.builder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             // no file watching, so we don't need a ResourceWatcherService
             .put(ScriptService.SCRIPT_AUTO_RELOAD_ENABLED_SETTING, false)
             .put("script." + PLUGIN_NAME + "_custom_globally_disabled_op", false)
diff --git a/core/src/test/java/org/elasticsearch/script/ScriptServiceTests.java b/core/src/test/java/org/elasticsearch/script/ScriptServiceTests.java
index caad93c68d..2028605d84 100644
--- a/core/src/test/java/org/elasticsearch/script/ScriptServiceTests.java
+++ b/core/src/test/java/org/elasticsearch/script/ScriptServiceTests.java
@@ -67,8 +67,8 @@ public class ScriptServiceTests extends ESTestCase {
     public void setup() throws IOException {
         Path genericConfigFolder = createTempDir();
         baseSettings = settingsBuilder()
-                .put("path.home", createTempDir().toString())
-                .put("path.conf", genericConfigFolder)
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+                .put(Environment.PATH_CONF_SETTING.getKey(), genericConfigFolder)
                 .build();
         resourceWatcherService = new ResourceWatcherService(baseSettings, null);
         scriptEngineService = new TestEngineService();
diff --git a/core/src/test/java/org/elasticsearch/search/builder/SearchSourceBuilderTests.java b/core/src/test/java/org/elasticsearch/search/builder/SearchSourceBuilderTests.java
index 5a1b99fe05..9597af9301 100644
--- a/core/src/test/java/org/elasticsearch/search/builder/SearchSourceBuilderTests.java
+++ b/core/src/test/java/org/elasticsearch/search/builder/SearchSourceBuilderTests.java
@@ -44,6 +44,7 @@ import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.query.AbstractQueryTestCase;
 import org.elasticsearch.index.query.EmptyQueryBuilder;
 import org.elasticsearch.index.query.QueryBuilders;
@@ -81,7 +82,7 @@ public class SearchSourceBuilderTests extends ESTestCase {
     public static void init() throws IOException {
         Settings settings = Settings.settingsBuilder()
                 .put("name", SearchSourceBuilderTests.class.toString())
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .build();
         namedWriteableRegistry = new NamedWriteableRegistry();
         injector = new ModulesBuilder().add(
diff --git a/core/src/test/java/org/elasticsearch/threadpool/SimpleThreadPoolIT.java b/core/src/test/java/org/elasticsearch/threadpool/SimpleThreadPoolIT.java
index 60f1bad608..ea225d9680 100644
--- a/core/src/test/java/org/elasticsearch/threadpool/SimpleThreadPoolIT.java
+++ b/core/src/test/java/org/elasticsearch/threadpool/SimpleThreadPoolIT.java
@@ -28,6 +28,7 @@ import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.json.JsonXContent;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.node.Node;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -186,7 +187,7 @@ public class SimpleThreadPoolIT extends ESIntegTestCase {
     public void testThreadPoolLeakingThreadsWithTribeNode() {
         Settings settings = Settings.builder()
                 .put("node.name", "thread_pool_leaking_threads_tribe_node")
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("tribe.t1.cluster.name", "non_existing_cluster")
                         //trigger initialization failure of one of the tribes (doesn't require starting the node)
                 .put("tribe.t1.plugin.mandatory", "non_existing").build();
diff --git a/core/src/test/java/org/elasticsearch/transport/netty/NettyTransportMultiPortIntegrationIT.java b/core/src/test/java/org/elasticsearch/transport/netty/NettyTransportMultiPortIntegrationIT.java
index ee49012291..f4dccc7716 100644
--- a/core/src/test/java/org/elasticsearch/transport/netty/NettyTransportMultiPortIntegrationIT.java
+++ b/core/src/test/java/org/elasticsearch/transport/netty/NettyTransportMultiPortIntegrationIT.java
@@ -28,6 +28,7 @@ import org.elasticsearch.common.network.NetworkModule;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.InetSocketTransportAddress;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESIntegTestCase.ClusterScope;
 import org.elasticsearch.test.ESIntegTestCase.Scope;
@@ -73,7 +74,7 @@ public class NettyTransportMultiPortIntegrationIT extends ESIntegTestCase {
         Settings settings = settingsBuilder()
                 .put("cluster.name", internalCluster().getClusterName())
                 .put(NetworkModule.TRANSPORT_TYPE_KEY, "netty")
-                .put("path.home", createTempDir().toString())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                 .build();
         try (TransportClient transportClient = TransportClient.builder().settings(settings).build()) {
             transportClient.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), randomPort));
diff --git a/modules/lang-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptedMetricTests.java b/modules/lang-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptedMetricTests.java
index 7e6dbd67f5..fb57c545c1 100644
--- a/modules/lang-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptedMetricTests.java
+++ b/modules/lang-groovy/src/test/java/org/elasticsearch/messy/tests/ScriptedMetricTests.java
@@ -23,6 +23,7 @@ import org.elasticsearch.action.index.IndexRequestBuilder;
 import org.elasticsearch.action.indexedscripts.put.PutIndexedScriptResponse;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.script.Script;
 import org.elasticsearch.script.ScriptService.ScriptType;
@@ -123,7 +124,7 @@ public class ScriptedMetricTests extends ESIntegTestCase {
     protected Settings nodeSettings(int nodeOrdinal) {
         Settings settings = Settings.settingsBuilder()
                 .put(super.nodeSettings(nodeOrdinal))
-                .put("path.conf", getDataPath("/org/elasticsearch/messy/tests/conf"))
+                .put(Environment.PATH_CONF_SETTING.getKey(), getDataPath("/org/elasticsearch/messy/tests/conf"))
                 .build();
         return settings;
     }
diff --git a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/RenderSearchTemplateTests.java b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/RenderSearchTemplateTests.java
index 4b3d3f3ff9..39b2f290cd 100644
--- a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/RenderSearchTemplateTests.java
+++ b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/RenderSearchTemplateTests.java
@@ -25,6 +25,7 @@ import org.elasticsearch.common.bytes.BytesReference;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.script.ScriptService.ScriptType;
 import org.elasticsearch.script.Template;
@@ -68,7 +69,7 @@ public class RenderSearchTemplateTests extends ESIntegTestCase {
             throw new RuntimeException(e);
         }
         return settingsBuilder().put(super.nodeSettings(nodeOrdinal))
-                .put("path.conf", configDir).build();
+                .put(Environment.PATH_CONF_SETTING.getKey(), configDir).build();
     }
 
     public void testInlineTemplate() {
diff --git a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryParserTests.java b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryParserTests.java
index 9d13680709..e005ca5b10 100644
--- a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryParserTests.java
+++ b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryParserTests.java
@@ -88,8 +88,8 @@ public class TemplateQueryParserTests extends ESTestCase {
     @Before
     public void setup() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir().toString())
-                .put("path.conf", this.getDataPath("config"))
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
+                .put(Environment.PATH_CONF_SETTING.getKey(), this.getDataPath("config"))
                 .put("name", getClass().getName())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
diff --git a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryTests.java b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryTests.java
index 70298266df..0914fd6cd7 100644
--- a/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryTests.java
+++ b/modules/lang-mustache/src/test/java/org/elasticsearch/messy/tests/TemplateQueryTests.java
@@ -31,6 +31,7 @@ import org.elasticsearch.common.ParseFieldMatcher;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentParser;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.index.query.TemplateQueryBuilder;
 import org.elasticsearch.index.query.TemplateQueryParser;
@@ -85,7 +86,7 @@ public class TemplateQueryTests extends ESIntegTestCase {
     @Override
     public Settings nodeSettings(int nodeOrdinal) {
         return settingsBuilder().put(super.nodeSettings(nodeOrdinal))
-                .put("path.conf", this.getDataPath("config")).build();
+                .put(Environment.PATH_CONF_SETTING.getKey(), this.getDataPath("config")).build();
     }
 
     public void testTemplateInBody() throws IOException {
diff --git a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuAnalysisTests.java b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuAnalysisTests.java
index d4b2530dbb..efd60427e2 100644
--- a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuAnalysisTests.java
+++ b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuAnalysisTests.java
@@ -20,6 +20,7 @@
 package org.elasticsearch.index.analysis;
 
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 
 import java.io.IOException;
@@ -32,7 +33,7 @@ import static org.hamcrest.Matchers.instanceOf;
 public class SimpleIcuAnalysisTests extends ESTestCase {
     public void testDefaultsIcuAnalysis() throws IOException {
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         AnalysisService analysisService = createAnalysisService(settings);
 
         TokenizerFactory tokenizerFactory = analysisService.tokenizer("icu_tokenizer");
diff --git a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuCollationTokenFilterTests.java b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuCollationTokenFilterTests.java
index 33c1f337db..632f3f539d 100644
--- a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuCollationTokenFilterTests.java
+++ b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuCollationTokenFilterTests.java
@@ -27,6 +27,7 @@ import org.apache.lucene.analysis.Tokenizer;
 import org.apache.lucene.analysis.core.KeywordTokenizer;
 import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 
 import java.io.IOException;
@@ -45,7 +46,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testBasicUsage() throws Exception {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "tr")
                 .put("index.analysis.filter.myCollator.strength", "primary")
@@ -61,7 +62,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testNormalization() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "tr")
                 .put("index.analysis.filter.myCollator.strength", "primary")
@@ -78,7 +79,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testSecondaryStrength() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.strength", "secondary")
@@ -96,7 +97,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testIgnorePunctuation() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.strength", "primary")
@@ -114,7 +115,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testIgnoreWhitespace() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.strength", "primary")
@@ -135,7 +136,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testNumerics() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.numeric", "true")
@@ -152,7 +153,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testIgnoreAccentsButNotCase() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.strength", "primary")
@@ -173,7 +174,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
     */
     public void testUpperCaseFirst() throws IOException {
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.language", "en")
                 .put("index.analysis.filter.myCollator.strength", "tertiary")
@@ -203,7 +204,7 @@ public class SimpleIcuCollationTokenFilterTests extends ESTestCase {
         String tailoredRules = tailoredCollator.getRules();
 
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myCollator.type", "icu_collation")
                 .put("index.analysis.filter.myCollator.rules", tailoredRules)
                 .put("index.analysis.filter.myCollator.strength", "primary")
diff --git a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuNormalizerCharFilterTests.java b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuNormalizerCharFilterTests.java
index acdbd9d4df..7ebb783d1d 100644
--- a/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuNormalizerCharFilterTests.java
+++ b/plugins/analysis-icu/src/test/java/org/elasticsearch/index/analysis/SimpleIcuNormalizerCharFilterTests.java
@@ -22,6 +22,7 @@ package org.elasticsearch.index.analysis;
 import com.ibm.icu.text.Normalizer2;
 import org.apache.lucene.analysis.CharFilter;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
 
 import java.io.StringReader;
@@ -34,7 +35,7 @@ import static org.elasticsearch.index.analysis.AnalysisTestUtils.createAnalysisS
 public class SimpleIcuNormalizerCharFilterTests extends ESTestCase {
     public void testDefaultSetting() throws Exception {
         Settings settings = Settings.settingsBuilder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .put("index.analysis.char_filter.myNormalizerChar.type", "icu_normalizer")
             .build();
         AnalysisService analysisService = createAnalysisService(settings);
@@ -57,7 +58,7 @@ public class SimpleIcuNormalizerCharFilterTests extends ESTestCase {
 
     public void testNameAndModeSetting() throws Exception {
         Settings settings = Settings.settingsBuilder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .put("index.analysis.char_filter.myNormalizerChar.type", "icu_normalizer")
             .put("index.analysis.char_filter.myNormalizerChar.name", "nfkc")
             .put("index.analysis.char_filter.myNormalizerChar.mode", "decompose")
diff --git a/plugins/analysis-kuromoji/src/test/java/org/elasticsearch/index/analysis/KuromojiAnalysisTests.java b/plugins/analysis-kuromoji/src/test/java/org/elasticsearch/index/analysis/KuromojiAnalysisTests.java
index 6312284210..016053810d 100644
--- a/plugins/analysis-kuromoji/src/test/java/org/elasticsearch/index/analysis/KuromojiAnalysisTests.java
+++ b/plugins/analysis-kuromoji/src/test/java/org/elasticsearch/index/analysis/KuromojiAnalysisTests.java
@@ -199,7 +199,7 @@ public class KuromojiAnalysisTests extends ESTestCase {
 
         String json = "/org/elasticsearch/index/analysis/kuromoji_analysis.json";
         Settings settings = Settings.settingsBuilder()
-                .put("path.home", home)
+                .put(Environment.PATH_HOME_SETTING.getKey(), home)
                 .loadFromStream(json, getClass().getResourceAsStream(json))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
diff --git a/plugins/analysis-phonetic/src/test/java/org/elasticsearch/index/analysis/SimplePhoneticAnalysisTests.java b/plugins/analysis-phonetic/src/test/java/org/elasticsearch/index/analysis/SimplePhoneticAnalysisTests.java
index b0a93f10e4..6dd341346e 100644
--- a/plugins/analysis-phonetic/src/test/java/org/elasticsearch/index/analysis/SimplePhoneticAnalysisTests.java
+++ b/plugins/analysis-phonetic/src/test/java/org/elasticsearch/index/analysis/SimplePhoneticAnalysisTests.java
@@ -48,7 +48,7 @@ public class SimplePhoneticAnalysisTests extends ESTestCase {
         String yaml = "/org/elasticsearch/index/analysis/phonetic-1.yml";
         Settings settings = settingsBuilder().loadFromStream(yaml, getClass().getResourceAsStream(yaml))
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .build();
         AnalysisService analysisService = testSimpleConfiguration(settings);
         TokenFilterFactory filterFactory = analysisService.tokenFilter("phonetic");
diff --git a/plugins/analysis-smartcn/src/test/java/org/elasticsearch/index/analysis/SimpleSmartChineseAnalysisTests.java b/plugins/analysis-smartcn/src/test/java/org/elasticsearch/index/analysis/SimpleSmartChineseAnalysisTests.java
index 55c0912b70..d33d36d4c6 100644
--- a/plugins/analysis-smartcn/src/test/java/org/elasticsearch/index/analysis/SimpleSmartChineseAnalysisTests.java
+++ b/plugins/analysis-smartcn/src/test/java/org/elasticsearch/index/analysis/SimpleSmartChineseAnalysisTests.java
@@ -47,7 +47,7 @@ public class SimpleSmartChineseAnalysisTests extends ESTestCase {
     public void testDefaultsIcuAnalysis() throws IOException {
         Index index = new Index("test");
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
         AnalysisModule analysisModule = new AnalysisModule(new Environment(settings));
diff --git a/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/PolishAnalysisTests.java b/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/PolishAnalysisTests.java
index 02fcbd0c36..05c7252bdf 100644
--- a/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/PolishAnalysisTests.java
+++ b/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/PolishAnalysisTests.java
@@ -50,7 +50,7 @@ public class PolishAnalysisTests extends ESTestCase {
     public void testDefaultsPolishAnalysis() throws IOException {
         Index index = new Index("test");
         Settings settings = settingsBuilder()
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
                 .build();
 
diff --git a/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/SimplePolishTokenFilterTests.java b/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/SimplePolishTokenFilterTests.java
index e091b0a0d9..306a835c36 100644
--- a/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/SimplePolishTokenFilterTests.java
+++ b/plugins/analysis-stempel/src/test/java/org/elasticsearch/index/analysis/SimplePolishTokenFilterTests.java
@@ -59,7 +59,7 @@ public class SimplePolishTokenFilterTests extends ESTestCase {
         Index index = new Index("test");
         Settings settings = Settings.settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .put("index.analysis.filter.myStemmer.type", "polish_stem")
                 .build();
         AnalysisService analysisService = createAnalysisService(index, settings);
@@ -81,7 +81,7 @@ public class SimplePolishTokenFilterTests extends ESTestCase {
         Index index = new Index("test");
         Settings settings = Settings.settingsBuilder()
                 .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT)
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .build();
         AnalysisService analysisService = createAnalysisService(index, settings);
 
diff --git a/plugins/discovery-azure/src/test/java/org/elasticsearch/cloud/azure/AbstractAzureTestCase.java b/plugins/discovery-azure/src/test/java/org/elasticsearch/cloud/azure/AbstractAzureTestCase.java
index 9747543a77..ad7140f502 100644
--- a/plugins/discovery-azure/src/test/java/org/elasticsearch/cloud/azure/AbstractAzureTestCase.java
+++ b/plugins/discovery-azure/src/test/java/org/elasticsearch/cloud/azure/AbstractAzureTestCase.java
@@ -23,6 +23,7 @@ import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.PathUtils;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.SettingsException;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugin.discovery.azure.AzureDiscoveryPlugin;
 import org.elasticsearch.plugins.Plugin;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -54,7 +55,7 @@ public abstract class AbstractAzureTestCase extends ESIntegTestCase {
 
     protected Settings readSettingsFromFile() {
         Settings.Builder settings = Settings.builder();
-        settings.put("path.home", createTempDir());
+        settings.put(Environment.PATH_HOME_SETTING.getKey(), createTempDir());
 
         // if explicit, just load it and don't load from env
         try {
diff --git a/plugins/discovery-ec2/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java b/plugins/discovery-ec2/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
index ec9155c51b..e5931dc8b8 100644
--- a/plugins/discovery-ec2/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
+++ b/plugins/discovery-ec2/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
@@ -23,6 +23,7 @@ import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.PathUtils;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.SettingsException;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugin.discovery.ec2.Ec2DiscoveryPlugin;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESIntegTestCase.ThirdParty;
@@ -40,7 +41,7 @@ public abstract class AbstractAwsTestCase extends ESIntegTestCase {
     protected Settings nodeSettings(int nodeOrdinal) {
                 Settings.Builder settings = Settings.builder()
                 .put(super.nodeSettings(nodeOrdinal))
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .extendArray("plugin.types", Ec2DiscoveryPlugin.class.getName())
                 .put("cloud.aws.test.random", randomInt())
                 .put("cloud.aws.test.write_failures", 0.1)
diff --git a/plugins/mapper-attachments/src/test/java/org/elasticsearch/mapper/attachments/AttachmentUnitTestCase.java b/plugins/mapper-attachments/src/test/java/org/elasticsearch/mapper/attachments/AttachmentUnitTestCase.java
index 9b7d8afe38..81a82825f8 100644
--- a/plugins/mapper-attachments/src/test/java/org/elasticsearch/mapper/attachments/AttachmentUnitTestCase.java
+++ b/plugins/mapper-attachments/src/test/java/org/elasticsearch/mapper/attachments/AttachmentUnitTestCase.java
@@ -22,6 +22,7 @@ package org.elasticsearch.mapper.attachments;
 import org.elasticsearch.Version;
 import org.elasticsearch.cluster.metadata.IndexMetaData;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.indices.IndicesModule;
 import org.elasticsearch.test.ESTestCase;
 import org.junit.Before;
@@ -39,7 +40,7 @@ public class AttachmentUnitTestCase extends ESTestCase {
     @Before
     public void createSettings() throws Exception {
       testSettings = Settings.builder()
-                             .put("path.home", createTempDir())
+                             .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                              .put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT.id)
                              .build();
     }
diff --git a/plugins/mapper-murmur3/src/test/java/org/elasticsearch/index/mapper/murmur3/Murmur3FieldMapperUpgradeTests.java b/plugins/mapper-murmur3/src/test/java/org/elasticsearch/index/mapper/murmur3/Murmur3FieldMapperUpgradeTests.java
index b3ad01bae4..fe12cb042d 100644
--- a/plugins/mapper-murmur3/src/test/java/org/elasticsearch/index/mapper/murmur3/Murmur3FieldMapperUpgradeTests.java
+++ b/plugins/mapper-murmur3/src/test/java/org/elasticsearch/index/mapper/murmur3/Murmur3FieldMapperUpgradeTests.java
@@ -23,6 +23,7 @@ import org.apache.lucene.util.LuceneTestCase;
 import org.apache.lucene.util.TestUtil;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.plugin.mapper.MapperMurmur3Plugin;
 import org.elasticsearch.plugins.Plugin;
@@ -62,7 +63,7 @@ public class Murmur3FieldMapperUpgradeTests extends ESIntegTestCase {
 
         Path dataPath = createTempDir();
         Settings settings = Settings.builder()
-                .put("path.data", dataPath)
+                .put(Environment.PATH_DATA_SETTING.getKey(), dataPath)
                 .build();
         final String node = internalCluster().startDataOnlyNode(settings); // workaround for dangling index loading issue when node is master
         Path[] nodePaths = internalCluster().getInstance(NodeEnvironment.class, node).nodeDataPaths();
diff --git a/plugins/mapper-size/src/test/java/org/elasticsearch/index/mapper/size/SizeFieldMapperUpgradeTests.java b/plugins/mapper-size/src/test/java/org/elasticsearch/index/mapper/size/SizeFieldMapperUpgradeTests.java
index 4529111c16..a2af6df4e7 100644
--- a/plugins/mapper-size/src/test/java/org/elasticsearch/index/mapper/size/SizeFieldMapperUpgradeTests.java
+++ b/plugins/mapper-size/src/test/java/org/elasticsearch/index/mapper/size/SizeFieldMapperUpgradeTests.java
@@ -23,6 +23,7 @@ import org.apache.lucene.util.LuceneTestCase;
 import org.apache.lucene.util.TestUtil;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.plugin.mapper.MapperSizePlugin;
 import org.elasticsearch.plugins.Plugin;
@@ -63,7 +64,7 @@ public class SizeFieldMapperUpgradeTests extends ESIntegTestCase {
 
         Path dataPath = createTempDir();
         Settings settings = Settings.builder()
-                .put("path.data", dataPath)
+                .put(Environment.PATH_DATA_SETTING.getKey(), dataPath)
                 .build();
         final String node = internalCluster().startDataOnlyNode(settings); // workaround for dangling index loading issue when node is master
         Path[] nodePaths = internalCluster().getInstance(NodeEnvironment.class, node).nodeDataPaths();
diff --git a/plugins/repository-s3/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java b/plugins/repository-s3/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
index e823e8e668..bc3706263f 100644
--- a/plugins/repository-s3/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
+++ b/plugins/repository-s3/src/test/java/org/elasticsearch/cloud/aws/AbstractAwsTestCase.java
@@ -23,6 +23,7 @@ import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.io.PathUtils;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.SettingsException;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.plugin.repository.s3.S3RepositoryPlugin;
 import org.elasticsearch.test.ESIntegTestCase;
 import org.elasticsearch.test.ESIntegTestCase.ThirdParty;
@@ -40,7 +41,7 @@ public abstract class AbstractAwsTestCase extends ESIntegTestCase {
     protected Settings nodeSettings(int nodeOrdinal) {
                 Settings.Builder settings = Settings.builder()
                 .put(super.nodeSettings(nodeOrdinal))
-                .put("path.home", createTempDir())
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
                 .extendArray("plugin.types", S3RepositoryPlugin.class.getName(), TestAwsS3Service.TestPlugin.class.getName())
                 .put("cloud.aws.test.random", randomInt())
                 .put("cloud.aws.test.write_failures", 0.1)
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/bootstrap/EvilSecurityTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/bootstrap/EvilSecurityTests.java
index 695d2a4232..c213f18f33 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/bootstrap/EvilSecurityTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/bootstrap/EvilSecurityTests.java
@@ -36,14 +36,14 @@ import java.util.Set;
 
 @SuppressForbidden(reason = "modifies system properties and attempts to create symbolic links intentionally")
 public class EvilSecurityTests extends ESTestCase {
-    
+
     /** test generated permissions */
     public void testGeneratedPermissions() throws Exception {
         Path path = createTempDir();
         // make a fake ES home and ensure we only grant permissions to that.
         Path esHome = path.resolve("esHome");
         Settings.Builder settingsBuilder = Settings.builder();
-        settingsBuilder.put("path.home", esHome.toString());
+        settingsBuilder.put(Environment.PATH_HOME_SETTING.getKey(), esHome.toString());
         Settings settings = settingsBuilder.build();
 
         Path fakeTmpDir = createTempDir();
@@ -56,7 +56,7 @@ public class EvilSecurityTests extends ESTestCase {
         } finally {
             System.setProperty("java.io.tmpdir", realTmpDir);
         }
-      
+
         // the fake es home
         assertNoPermissions(esHome, permissions);
         // its parent
@@ -74,14 +74,14 @@ public class EvilSecurityTests extends ESTestCase {
         Path esHome = path.resolve("esHome");
 
         Settings.Builder settingsBuilder = Settings.builder();
-        settingsBuilder.put("path.home", esHome.resolve("home").toString());
-        settingsBuilder.put("path.conf", esHome.resolve("conf").toString());
-        settingsBuilder.put("path.scripts", esHome.resolve("scripts").toString());
-        settingsBuilder.put("path.plugins", esHome.resolve("plugins").toString());
-        settingsBuilder.putArray("path.data", esHome.resolve("data1").toString(), esHome.resolve("data2").toString());
-        settingsBuilder.put("path.shared_data", esHome.resolve("custom").toString());
-        settingsBuilder.put("path.logs", esHome.resolve("logs").toString());
-        settingsBuilder.put("pidfile", esHome.resolve("test.pid").toString());
+        settingsBuilder.put(Environment.PATH_HOME_SETTING.getKey(), esHome.resolve("home").toString());
+        settingsBuilder.put(Environment.PATH_CONF_SETTING.getKey(), esHome.resolve("conf").toString());
+        settingsBuilder.put(Environment.PATH_SCRIPTS_SETTING.getKey(), esHome.resolve("scripts").toString());
+        settingsBuilder.put(Environment.PATH_PLUGINS_SETTING.getKey(), esHome.resolve("plugins").toString());
+        settingsBuilder.putArray(Environment.PATH_DATA_SETTING.getKey(), esHome.resolve("data1").toString(), esHome.resolve("data2").toString());
+        settingsBuilder.put(Environment.PATH_SHARED_DATA_SETTING.getKey(), esHome.resolve("custom").toString());
+        settingsBuilder.put(Environment.PATH_LOGS_SETTING.getKey(), esHome.resolve("logs").toString());
+        settingsBuilder.put(Environment.PIDFILE_SETTING.getKey(), esHome.resolve("test.pid").toString());
         Settings settings = settingsBuilder.build();
 
         Path fakeTmpDir = createTempDir();
@@ -104,7 +104,7 @@ public class EvilSecurityTests extends ESTestCase {
         assertNoPermissions(esHome.getParent().resolve("other"), permissions);
         // double check we overwrote java.io.tmpdir correctly for the test
         assertNoPermissions(PathUtils.get(realTmpDir), permissions);
- 
+
         // check that all directories got permissions:
 
         // bin file: ro
@@ -135,10 +135,10 @@ public class EvilSecurityTests extends ESTestCase {
         // PID file: delete only (for the shutdown hook)
         assertExactPermissions(new FilePermission(environment.pidFile().toString(), "delete"), permissions);
     }
-    
+
     public void testEnsureSymlink() throws IOException {
         Path p = createTempDir();
-        
+
         Path exists = p.resolve("exists");
         Files.createDirectory(exists);
 
@@ -154,7 +154,7 @@ public class EvilSecurityTests extends ESTestCase {
         Security.ensureDirectoryExists(linkExists);
         Files.createTempFile(linkExists, null, null);
     }
-    
+
     public void testEnsureBrokenSymlink() throws IOException {
         Path p = createTempDir();
 
@@ -199,7 +199,7 @@ public class EvilSecurityTests extends ESTestCase {
         assertExactPermissions(new FilePermission(target.resolve("foo").toString(), "read"), permissions);
     }
 
-    /** 
+    /**
      * checks exact file permissions, meaning those and only those for that path.
      */
     static void assertExactPermissions(FilePermission expected, PermissionCollection actual) {
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/common/cli/CheckFileCommandTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/common/cli/CheckFileCommandTests.java
index 8633511756..45f3df22cd 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/common/cli/CheckFileCommandTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/common/cli/CheckFileCommandTests.java
@@ -124,7 +124,7 @@ public class CheckFileCommandTests extends ESTestCase {
         try (FileSystem fs = Jimfs.newFileSystem(configuration)) {
             Path path = fs.getPath(randomAsciiOfLength(10));
             Settings settings = Settings.builder()
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             new CreateFileCommand(captureOutputTerminal, path).execute(settings, new Environment(settings));
             assertThat(Files.exists(path), is(true));
@@ -141,7 +141,7 @@ public class CheckFileCommandTests extends ESTestCase {
             Files.write(path, "anything".getBytes(StandardCharsets.UTF_8));
 
             Settings settings = Settings.builder()
-                    .put("path.home", createTempDir().toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toString())
                     .build();
             new DeleteFileCommand(captureOutputTerminal, path).execute(settings, new Environment(settings));
             assertThat(Files.exists(path), is(false));
@@ -173,7 +173,7 @@ public class CheckFileCommandTests extends ESTestCase {
             this.fs = fs;
             this.paths = new Path[] { writePath(fs, "p1", "anything"), writePath(fs, "p2", "anything"), writePath(fs, "p3", "anything") };
             Settings settings = Settings.settingsBuilder()
-                    .put("path.home", baseDir.toString())
+                    .put(Environment.PATH_HOME_SETTING.getKey(), baseDir.toString())
                     .build();
             return super.execute(Settings.EMPTY, new Environment(settings));
         }
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/node/internal/EvilInternalSettingsPreparerTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/node/internal/EvilInternalSettingsPreparerTests.java
index 3789c273cf..d2c8ccfd3c 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/node/internal/EvilInternalSettingsPreparerTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/node/internal/EvilInternalSettingsPreparerTests.java
@@ -72,7 +72,7 @@ public class EvilInternalSettingsPreparerTests extends ESTestCase {
     @Before
     public void createBaseEnvSettings() {
         baseEnvSettings = settingsBuilder()
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             .build();
     }
 
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerPermissionTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerPermissionTests.java
index 0eebc9731f..5e70cf7192 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerPermissionTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerPermissionTests.java
@@ -70,13 +70,13 @@ public class PluginManagerPermissionTests extends ESTestCase {
     @Before
     public void setup() {
         Path tempDir = createTempDir();
-        Settings.Builder settingsBuilder = settingsBuilder().put("path.home", tempDir);
+        Settings.Builder settingsBuilder = settingsBuilder().put(Environment.PATH_HOME_SETTING.getKey(), tempDir);
         if (randomBoolean()) {
-            settingsBuilder.put("path.plugins", createTempDir());
+            settingsBuilder.put(Environment.PATH_PLUGINS_SETTING.getKey(), createTempDir());
         }
 
         if (randomBoolean()) {
-            settingsBuilder.put("path.conf", createTempDir());
+            settingsBuilder.put(Environment.PATH_CONF_SETTING.getKey(), createTempDir());
         }
 
         environment = new Environment(settingsBuilder.build());
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerTests.java
index 514a2ee671..24055d9f6d 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerTests.java
@@ -108,7 +108,7 @@ public class PluginManagerTests extends ESIntegTestCase {
     @Before
     public void setup() throws Exception {
         environment = buildInitialSettings();
-        System.setProperty("es.default.path.home", environment.settings().get("path.home"));
+        System.setProperty("es.default.path.home", Environment.PATH_HOME_SETTING.get(environment.settings()));
         Path binDir = environment.binFile();
         if (!Files.exists(binDir)) {
             Files.createDirectories(binDir);
@@ -696,7 +696,7 @@ public class PluginManagerTests extends ESIntegTestCase {
     private Environment buildInitialSettings() throws IOException {
         Settings settings = settingsBuilder()
                 .put("http.enabled", true)
-                .put("path.home", createTempDir()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         return InternalSettingsPreparer.prepareEnvironment(settings, null);
     }
 
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerUnitTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerUnitTests.java
index 266b44ebfb..49edcc7b1d 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerUnitTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/plugins/PluginManagerUnitTests.java
@@ -56,8 +56,8 @@ public class PluginManagerUnitTests extends ESTestCase {
         Path genericConfigFolder = createTempDir();
 
         Settings settings = settingsBuilder()
-                .put("path.conf", genericConfigFolder)
-                .put("path.home", homeFolder)
+                .put(Environment.PATH_CONF_SETTING.getKey(), genericConfigFolder)
+                .put(Environment.PATH_HOME_SETTING.getKey(), homeFolder)
                 .build();
         Environment environment = new Environment(settings);
 
diff --git a/qa/evil-tests/src/test/java/org/elasticsearch/tribe/TribeUnitTests.java b/qa/evil-tests/src/test/java/org/elasticsearch/tribe/TribeUnitTests.java
index 1ad972e10e..fb01f9b9b3 100644
--- a/qa/evil-tests/src/test/java/org/elasticsearch/tribe/TribeUnitTests.java
+++ b/qa/evil-tests/src/test/java/org/elasticsearch/tribe/TribeUnitTests.java
@@ -25,6 +25,7 @@ import org.elasticsearch.cluster.node.DiscoveryNode;
 import org.elasticsearch.common.SuppressForbidden;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.discovery.DiscoveryService;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.node.Node;
 import org.elasticsearch.node.internal.InternalSettingsPreparer;
 import org.elasticsearch.test.ESIntegTestCase;
@@ -56,7 +57,7 @@ public class TribeUnitTests extends ESTestCase {
         Settings baseSettings = Settings.builder()
             .put("http.enabled", false)
             .put("node.mode", NODE_MODE)
-            .put("path.home", createTempDir()).build();
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
 
         tribe1 = new TribeClientNode(
             Settings.builder()
@@ -102,7 +103,11 @@ public class TribeUnitTests extends ESTestCase {
 
     public void testThatTribeClientsIgnoreGlobalConfig() throws Exception {
         Path pathConf = getDataPath("elasticsearch.yml").getParent();
-        Settings settings = Settings.builder().put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true).put("path.conf", pathConf).build();
+        Settings settings = Settings
+            .builder()
+            .put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true)
+            .put(Environment.PATH_CONF_SETTING.getKey(), pathConf)
+            .build();
         assertTribeNodeSuccesfullyCreated(settings);
     }
 
@@ -111,7 +116,7 @@ public class TribeUnitTests extends ESTestCase {
         //they can find their corresponding tribes using the proper transport
         Settings settings = Settings.builder().put("http.enabled", false).put("node.name", "tribe_node")
                 .put("tribe.t1.node.mode", NODE_MODE).put("tribe.t2.node.mode", NODE_MODE)
-                .put("path.home", createTempDir()).put(extraSettings).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).put(extraSettings).build();
 
         try (Node node = new Node(settings).start()) {
             try (Client client = node.client()) {
diff --git a/qa/smoke-test-client/src/test/java/org/elasticsearch/smoketest/ESSmokeClientTestCase.java b/qa/smoke-test-client/src/test/java/org/elasticsearch/smoketest/ESSmokeClientTestCase.java
index 227936beb4..3fea66459c 100644
--- a/qa/smoke-test-client/src/test/java/org/elasticsearch/smoketest/ESSmokeClientTestCase.java
+++ b/qa/smoke-test-client/src/test/java/org/elasticsearch/smoketest/ESSmokeClientTestCase.java
@@ -28,6 +28,7 @@ import org.elasticsearch.common.logging.ESLoggerFactory;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.InetSocketTransportAddress;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.node.internal.InternalSettingsPreparer;
 import org.junit.After;
 import org.junit.AfterClass;
@@ -79,7 +80,7 @@ public abstract class ESSmokeClientTestCase extends LuceneTestCase {
                 .put("name", "qa_smoke_client_" + counter.getAndIncrement())
                 .put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true) // prevents any settings to be replaced by system properties.
                 .put("client.transport.ignore_cluster_name", true)
-                .put("path.home", tempDir)
+                .put(Environment.PATH_HOME_SETTING.getKey(), tempDir)
                 .put("node.mode", "network").build(); // we require network here!
 
         TransportClient.Builder transportClientBuilder = TransportClient.builder().settings(clientSettings);
diff --git a/test/framework/src/main/java/org/elasticsearch/index/MapperTestUtils.java b/test/framework/src/main/java/org/elasticsearch/index/MapperTestUtils.java
index 1c110bc405..a9b45a5b33 100644
--- a/test/framework/src/main/java/org/elasticsearch/index/MapperTestUtils.java
+++ b/test/framework/src/main/java/org/elasticsearch/index/MapperTestUtils.java
@@ -45,7 +45,7 @@ public class MapperTestUtils {
 
     public static MapperService newMapperService(Path tempDir, Settings settings, IndicesModule indicesModule) throws IOException {
         Settings.Builder settingsBuilder = Settings.builder()
-            .put("path.home", tempDir)
+            .put(Environment.PATH_HOME_SETTING.getKey(), tempDir)
             .put(settings);
         if (settings.get(IndexMetaData.SETTING_VERSION_CREATED) == null) {
             settingsBuilder.put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT);
diff --git a/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java b/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
index ff09ba0e8f..2fc298048c 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/ESIntegTestCase.java
@@ -2091,11 +2091,11 @@ public abstract class ESIntegTestCase extends ESTestCase {
         assertTrue(Files.exists(dest));
         Settings.Builder builder = Settings.builder()
                 .put(settings)
-                .put("path.data", dataDir.toAbsolutePath());
+                .put(Environment.PATH_DATA_SETTING.getKey(), dataDir.toAbsolutePath());
 
         Path configDir = indexDir.resolve("config");
         if (Files.exists(configDir)) {
-            builder.put("path.conf", configDir.toAbsolutePath());
+            builder.put(Environment.PATH_CONF_SETTING.getKey(), configDir.toAbsolutePath());
         }
         return builder.build();
     }
diff --git a/test/framework/src/main/java/org/elasticsearch/test/ESSingleNodeTestCase.java b/test/framework/src/main/java/org/elasticsearch/test/ESSingleNodeTestCase.java
index 9b06bae21b..f73839c5ce 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/ESSingleNodeTestCase.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/ESSingleNodeTestCase.java
@@ -36,6 +36,7 @@ import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.util.BigArrays;
 import org.elasticsearch.common.util.concurrent.EsExecutors;
 import org.elasticsearch.common.xcontent.XContentBuilder;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.index.IndexService;
 import org.elasticsearch.indices.IndicesService;
 import org.elasticsearch.node.MockNode;
@@ -158,10 +159,10 @@ public abstract class ESSingleNodeTestCase extends ESTestCase {
     private Node newNode() {
         Settings settings = Settings.builder()
             .put(ClusterName.SETTING, InternalTestCluster.clusterName("single-node-cluster", randomLong()))
-            .put("path.home", createTempDir())
+            .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir())
             // TODO: use a consistent data path for custom paths
             // This needs to tie into the ESIntegTestCase#indexSettings() method
-            .put("path.shared_data", createTempDir().getParent())
+            .put(Environment.PATH_SHARED_DATA_SETTING.getKey(), createTempDir().getParent())
             .put("node.name", nodeName())
             .put(IndexMetaData.SETTING_NUMBER_OF_SHARDS, 1)
             .put(IndexMetaData.SETTING_NUMBER_OF_REPLICAS, 0)
diff --git a/test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java b/test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java
index 3777653297..598b6216ce 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java
@@ -531,8 +531,8 @@ public abstract class ESTestCase extends LuceneTestCase {
     public NodeEnvironment newNodeEnvironment(Settings settings) throws IOException {
         Settings build = Settings.builder()
                 .put(settings)
-                .put("path.home", createTempDir().toAbsolutePath())
-                .putArray("path.data", tmpPaths()).build();
+                .put(Environment.PATH_HOME_SETTING.getKey(), createTempDir().toAbsolutePath())
+                .putArray(Environment.PATH_DATA_SETTING.getKey(), tmpPaths()).build();
         return new NodeEnvironment(build, new Environment(build));
     }
 
diff --git a/test/framework/src/main/java/org/elasticsearch/test/ExternalTestCluster.java b/test/framework/src/main/java/org/elasticsearch/test/ExternalTestCluster.java
index 34b6bfbfb1..0b3facca05 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/ExternalTestCluster.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/ExternalTestCluster.java
@@ -32,6 +32,7 @@ import org.elasticsearch.common.logging.Loggers;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.transport.InetSocketTransportAddress;
 import org.elasticsearch.common.transport.TransportAddress;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.node.internal.InternalSettingsPreparer;
 import org.elasticsearch.plugins.Plugin;
 
@@ -74,7 +75,7 @@ public final class ExternalTestCluster extends TestCluster {
                 .put("name", InternalTestCluster.TRANSPORT_CLIENT_PREFIX + EXTERNAL_CLUSTER_PREFIX + counter.getAndIncrement())
                 .put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true) // prevents any settings to be replaced by system properties.
                 .put("client.transport.ignore_cluster_name", true)
-                .put("path.home", tempDir)
+                .put(Environment.PATH_HOME_SETTING.getKey(), tempDir)
                 .put("node.mode", "network").build(); // we require network here!
 
         TransportClient.Builder transportClientBuilder = TransportClient.builder().settings(clientSettings);
diff --git a/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java b/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
index 3b772b4ef3..6fafb52164 100644
--- a/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
+++ b/test/framework/src/main/java/org/elasticsearch/test/InternalTestCluster.java
@@ -62,6 +62,7 @@ import org.elasticsearch.common.unit.ByteSizeValue;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.common.util.concurrent.EsExecutors;
 import org.elasticsearch.discovery.DiscoveryService;
+import org.elasticsearch.env.Environment;
 import org.elasticsearch.env.NodeEnvironment;
 import org.elasticsearch.http.HttpServerTransport;
 import org.elasticsearch.index.IndexModule;
@@ -286,12 +287,12 @@ public final class InternalTestCluster extends TestCluster {
                 for (int i = 0; i < numOfDataPaths; i++) {
                     dataPath.append(baseDir.resolve("d" + i).toAbsolutePath()).append(',');
                 }
-                builder.put("path.data", dataPath.toString());
+                builder.put(Environment.PATH_DATA_SETTING.getKey(), dataPath.toString());
             }
         }
-        builder.put("path.shared_data", baseDir.resolve("custom"));
-        builder.put("path.home", baseDir);
-        builder.put("path.repo", baseDir.resolve("repos"));
+        builder.put(Environment.PATH_SHARED_DATA_SETTING.getKey(), baseDir.resolve("custom"));
+        builder.put(Environment.PATH_HOME_SETTING.getKey(), baseDir);
+        builder.put(Environment.PATH_REPO_SETTING.getKey(), baseDir.resolve("repos"));
         builder.put("transport.tcp.port", TRANSPORT_BASE_PORT + "-" + (TRANSPORT_BASE_PORT + PORTS_PER_CLUSTER));
         builder.put("http.port", HTTP_BASE_PORT + "-" + (HTTP_BASE_PORT + PORTS_PER_CLUSTER));
         builder.put(InternalSettingsPreparer.IGNORE_SYSTEM_PROPERTIES_SETTING, true);
@@ -594,7 +595,7 @@ public final class InternalTestCluster extends TestCluster {
         String name = buildNodeName(nodeId);
         assert !nodes.containsKey(name);
         Settings finalSettings = settingsBuilder()
-                .put("path.home", baseDir) // allow overriding path.home
+                .put(Environment.PATH_HOME_SETTING.getKey(), baseDir) // allow overriding path.home
                 .put(settings)
                 .put("name", name)
                 .put(DiscoveryService.SETTING_DISCOVERY_SEED, seed)
@@ -890,7 +891,7 @@ public final class InternalTestCluster extends TestCluster {
             Settings nodeSettings = node.settings();
             Builder builder = settingsBuilder()
                     .put("client.transport.nodes_sampler_interval", "1s")
-                    .put("path.home", baseDir)
+                    .put(Environment.PATH_HOME_SETTING.getKey(), baseDir)
                     .put("name", TRANSPORT_CLIENT_PREFIX + node.settings().get("name"))
                     .put(ClusterName.SETTING, clusterName).put("client.transport.sniff", sniff)
                     .put("node.mode", nodeSettings.get("node.mode", nodeMode))