[TEST] Expect nodes getting disconnected quickly

If all nodes get disconnected before we can send the request we might
try to reconnect and that will fail with an ISE instead of the a transport
exception.

Closes #25301

1 files changed, 9 insertions, 5 deletions

diff --git a/core/src/test/java/org/elasticsearch/transport/RemoteClusterServiceTests.java b/core/src/test/java/org/elasticsearch/transport/RemoteClusterServiceTests.java
index 646efa9428..1dbd935229 100644
--- a/core/src/test/java/org/elasticsearch/transport/RemoteClusterServiceTests.java
+++ b/core/src/test/java/org/elasticsearch/transport/RemoteClusterServiceTests.java
@@ -410,12 +410,16 @@ public class RemoteClusterServiceTests extends ESTestCase {
                             });
                         failLatch.await();
                         assertNotNull(ex.get());
-                        if (ex.get() instanceof TransportException == false) {
-                            // we have an issue for this see #25301
-                            logger.error("expected TransportException but got a different one see #25301", ex.get());
+                        if (ex.get() instanceof  IllegalStateException) {
+                            assertEquals(ex.get().getMessage(), "no seed node left");
+                        } else {
+                            if (ex.get() instanceof TransportException == false) {
+                                // we have an issue for this see #25301
+                                logger.error("expected TransportException but got a different one see #25301", ex.get());
+                            }
+                            assertTrue("expected TransportException but got a different one [" + ex.get().getClass().toString() + "]",
+                                ex.get() instanceof TransportException);
                         }
-                        assertTrue("expected TransportException but got a different one [" + ex.get().getClass().toString() + "]",
-                            ex.get() instanceof TransportException);
                     }
                 }
             }