Add 2.9.1 release notes and changes documents

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+<!---
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+# distributed with this work for additional information
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+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
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+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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+# limitations under the License.
+-->
+# "Apache Hadoop" Changelog
+
+## Release 2.9.1 - 2018-04-16
+
+### INCOMPATIBLE CHANGES:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HDFS-12883](https://issues.apache.org/jira/browse/HDFS-12883) | RBF: Document Router and State Store metrics |  Major | documentation | Yiqun Lin | Yiqun Lin |
+| [HDFS-12895](https://issues.apache.org/jira/browse/HDFS-12895) | RBF: Add ACL support for mount table |  Major | . | Yiqun Lin | Yiqun Lin |
+| [YARN-7190](https://issues.apache.org/jira/browse/YARN-7190) | Ensure only NM classpath in 2.x gets TSv2 related hbase jars, not the user classpath |  Major | timelineclient, timelinereader, timelineserver | Vrushali C | Varun Saxena |
+| [HDFS-13099](https://issues.apache.org/jira/browse/HDFS-13099) | RBF: Use the ZooKeeper as the default State Store |  Minor | documentation | Yiqun Lin | Yiqun Lin |
+
+
+### IMPORTANT ISSUES:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HDFS-13083](https://issues.apache.org/jira/browse/HDFS-13083) | RBF: Fix doc error setting up client |  Major | federation | tartarus | tartarus |
+
+
+### NEW FEATURES:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-12756](https://issues.apache.org/jira/browse/HADOOP-12756) | Incorporate Aliyun OSS file system implementation |  Major | fs, fs/oss | shimingfei | mingfei.shi |
+
+
+### IMPROVEMENTS:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-14872](https://issues.apache.org/jira/browse/HADOOP-14872) | CryptoInputStream should implement unbuffer |  Major | fs, security | John Zhuge | John Zhuge |
+| [HADOOP-14964](https://issues.apache.org/jira/browse/HADOOP-14964) | AliyunOSS: backport Aliyun OSS module to branch-2 |  Major | fs/oss | Genmao Yu | SammiChen |
+| [YARN-6851](https://issues.apache.org/jira/browse/YARN-6851) | Capacity Scheduler: document configs for controlling # containers allowed to be allocated per node heartbeat |  Minor | . | Wei Yan | Wei Yan |
+| [YARN-7495](https://issues.apache.org/jira/browse/YARN-7495) | Improve robustness of the AggregatedLogDeletionService |  Major | log-aggregation | Jonathan Eagles | Jonathan Eagles |
+| [YARN-7611](https://issues.apache.org/jira/browse/YARN-7611) | Node manager web UI should display container type in containers page |  Major | nodemanager, webapp | Weiwei Yang | Weiwei Yang |
+| [HADOOP-15056](https://issues.apache.org/jira/browse/HADOOP-15056) | Fix TestUnbuffer#testUnbufferException failure |  Minor | test | Jack Bearden | Jack Bearden |
+| [HADOOP-15012](https://issues.apache.org/jira/browse/HADOOP-15012) | Add readahead, dropbehind, and unbuffer to StreamCapabilities |  Major | fs | John Zhuge | John Zhuge |
+| [HADOOP-15104](https://issues.apache.org/jira/browse/HADOOP-15104) | AliyunOSS: change the default value of max error retry |  Major | fs/oss | wujinhu | wujinhu |
+| [YARN-7642](https://issues.apache.org/jira/browse/YARN-7642) | Add test case to verify context update after container promotion or demotion with or without auto update |  Minor | nodemanager | Weiwei Yang | Weiwei Yang |
+| [HADOOP-15111](https://issues.apache.org/jira/browse/HADOOP-15111) | AliyunOSS: backport HADOOP-14993 to branch-2 |  Major | fs/oss | Genmao Yu | Genmao Yu |
+| [HDFS-9023](https://issues.apache.org/jira/browse/HDFS-9023) | When NN is not able to identify DN for replication, reason behind it can be logged |  Critical | hdfs-client, namenode | Surendra Singh Lilhore | Xiao Chen |
+| [YARN-7678](https://issues.apache.org/jira/browse/YARN-7678) | Ability to enable logging of container memory stats |  Major | nodemanager | Jim Brennan | Jim Brennan |
+| [HDFS-12945](https://issues.apache.org/jira/browse/HDFS-12945) | Switch to ClientProtocol instead of NamenodeProtocols in NamenodeWebHdfsMethods |  Minor | . | Wei Yan | Wei Yan |
+| [YARN-7590](https://issues.apache.org/jira/browse/YARN-7590) | Improve container-executor validation check |  Major | security, yarn | Eric Yang | Eric Yang |
+| [HADOOP-15189](https://issues.apache.org/jira/browse/HADOOP-15189) | backport HADOOP-15039 to branch-2 and branch-3 |  Blocker | . | Genmao Yu | Genmao Yu |
+| [HADOOP-15212](https://issues.apache.org/jira/browse/HADOOP-15212) | Add independent secret manager method for logging expired tokens |  Major | security | Daryn Sharp | Daryn Sharp |
+| [YARN-7728](https://issues.apache.org/jira/browse/YARN-7728) | Expose container preemptions related information in Capacity Scheduler queue metrics |  Major | . | Eric Payne | Eric Payne |
+| [MAPREDUCE-7048](https://issues.apache.org/jira/browse/MAPREDUCE-7048) | Uber AM can crash due to unknown task in statusUpdate |  Major | mr-am | Peter Bacsko | Peter Bacsko |
+| [HADOOP-13972](https://issues.apache.org/jira/browse/HADOOP-13972) | ADLS to support per-store configuration |  Major | fs/adl | John Zhuge | Sharad Sonker |
+| [YARN-7813](https://issues.apache.org/jira/browse/YARN-7813) | Capacity Scheduler Intra-queue Preemption should be configurable for each queue |  Major | capacity scheduler, scheduler preemption | Eric Payne | Eric Payne |
+| [HDFS-11187](https://issues.apache.org/jira/browse/HDFS-11187) | Optimize disk access for last partial chunk checksum of Finalized replica |  Major | datanode | Wei-Chiu Chuang | Gabor Bota |
+| [HADOOP-15279](https://issues.apache.org/jira/browse/HADOOP-15279) | increase maven heap size recommendations |  Minor | build, documentation, test | Allen Wittenauer | Allen Wittenauer |
+| [HDFS-12884](https://issues.apache.org/jira/browse/HDFS-12884) | BlockUnderConstructionFeature.truncateBlock should be of type BlockInfo |  Major | namenode | Konstantin Shvachko | chencan |
+| [HADOOP-15334](https://issues.apache.org/jira/browse/HADOOP-15334) | Upgrade Maven surefire plugin |  Major | build | Arpit Agarwal | Arpit Agarwal |
+| [YARN-7623](https://issues.apache.org/jira/browse/YARN-7623) | Fix the CapacityScheduler Queue configuration documentation |  Major | . | Arun Suresh | Jonathan Hung |
+| [HDFS-13314](https://issues.apache.org/jira/browse/HDFS-13314) | NameNode should optionally exit if it detects FsImage corruption |  Major | namenode | Arpit Agarwal | Arpit Agarwal |
+
+
+### BUG FIXES:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-13723](https://issues.apache.org/jira/browse/HADOOP-13723) | AliyunOSSInputStream#read() should update read bytes stat correctly |  Major | tools | Mingliang Liu | Mingliang Liu |
+| [HADOOP-14045](https://issues.apache.org/jira/browse/HADOOP-14045) | Aliyun OSS documentation missing from website |  Major | documentation, fs/oss | Andrew Wang | Yiqun Lin |
+| [HADOOP-14458](https://issues.apache.org/jira/browse/HADOOP-14458) | Add missing imports to TestAliyunOSSFileSystemContract.java |  Trivial | fs/oss, test | Mingliang Liu | Mingliang Liu |
+| [HADOOP-14466](https://issues.apache.org/jira/browse/HADOOP-14466) | Remove useless document from TestAliyunOSSFileSystemContract.java |  Minor | documentation | Akira Ajisaka | Chen Liang |
+| [HDFS-12318](https://issues.apache.org/jira/browse/HDFS-12318) | Fix IOException condition for openInfo in DFSInputStream |  Major | . | legend | legend |
+| [HDFS-12614](https://issues.apache.org/jira/browse/HDFS-12614) | FSPermissionChecker#getINodeAttrs() throws NPE when INodeAttributesProvider configured |  Major | . | Manoj Govindassamy | Manoj Govindassamy |
+| [HDFS-12788](https://issues.apache.org/jira/browse/HDFS-12788) | Reset the upload button when file upload fails |  Critical | ui, webhdfs | Brahma Reddy Battula | Brahma Reddy Battula |
+| [YARN-7388](https://issues.apache.org/jira/browse/YARN-7388) | TestAMRestart should be scheduler agnostic |  Major | . | Haibo Chen | Haibo Chen |
+| [HDFS-12705](https://issues.apache.org/jira/browse/HDFS-12705) | WebHdfsFileSystem exceptions should retain the caused by exception |  Major | hdfs | Daryn Sharp | Hanisha Koneru |
+| [YARN-7361](https://issues.apache.org/jira/browse/YARN-7361) | Improve the docker container runtime documentation |  Major | . | Shane Kumpf | Shane Kumpf |
+| [YARN-7469](https://issues.apache.org/jira/browse/YARN-7469) | Capacity Scheduler Intra-queue preemption: User can starve if newest app is exactly at user limit |  Major | capacity scheduler, yarn | Eric Payne | Eric Payne |
+| [YARN-7489](https://issues.apache.org/jira/browse/YARN-7489) | ConcurrentModificationException in RMAppImpl#getRMAppMetrics |  Major | capacityscheduler | Tao Yang | Tao Yang |
+| [YARN-7525](https://issues.apache.org/jira/browse/YARN-7525) | Incorrect query parameters in cluster nodes REST API document |  Minor | documentation | Tao Yang | Tao Yang |
+| [HADOOP-15045](https://issues.apache.org/jira/browse/HADOOP-15045) | ISA-L build options are documented in branch-2 |  Major | build, documentation | Akira Ajisaka | Akira Ajisaka |
+| [YARN-7390](https://issues.apache.org/jira/browse/YARN-7390) | All reservation related test cases failed when TestYarnClient runs against Fair Scheduler. |  Major | fairscheduler, reservation system | Yufei Gu | Yufei Gu |
+| [HDFS-12754](https://issues.apache.org/jira/browse/HDFS-12754) | Lease renewal can hit a deadlock |  Major | . | Kuhu Shukla | Kuhu Shukla |
+| [HDFS-12832](https://issues.apache.org/jira/browse/HDFS-12832) | INode.getFullPathName may throw ArrayIndexOutOfBoundsException lead to NameNode exit |  Critical | namenode | DENG FEI | Konstantin Shvachko |
+| [HDFS-11754](https://issues.apache.org/jira/browse/HDFS-11754) | Make FsServerDefaults cache configurable. |  Minor | . | Rushabh S Shah | Mikhail Erofeev |
+| [YARN-7509](https://issues.apache.org/jira/browse/YARN-7509) | AsyncScheduleThread and ResourceCommitterService are still running after RM is transitioned to standby |  Critical | . | Tao Yang | Tao Yang |
+| [YARN-7558](https://issues.apache.org/jira/browse/YARN-7558) | "yarn logs" command fails to get logs for running containers if UI authentication is enabled. |  Critical | . | Namit Maheshwari | Xuan Gong |
+| [HDFS-12638](https://issues.apache.org/jira/browse/HDFS-12638) | Delete copy-on-truncate block along with the original block, when deleting a file being truncated |  Blocker | hdfs | Jiandan Yang | Konstantin Shvachko |
+| [MAPREDUCE-5124](https://issues.apache.org/jira/browse/MAPREDUCE-5124) | AM lacks flow control for task events |  Major | mr-am | Jason Lowe | Peter Bacsko |
+| [YARN-7455](https://issues.apache.org/jira/browse/YARN-7455) | quote\_and\_append\_arg can overflow buffer |  Major | nodemanager | Jason Lowe | Jim Brennan |
+| [HADOOP-14985](https://issues.apache.org/jira/browse/HADOOP-14985) | Remove subversion related code from VersionInfoMojo.java |  Minor | build | Akira Ajisaka | Ajay Kumar |
+| [HDFS-12889](https://issues.apache.org/jira/browse/HDFS-12889) | Router UI is missing robots.txt file |  Major | . | Bharat Viswanadham | Bharat Viswanadham |
+| [HDFS-11576](https://issues.apache.org/jira/browse/HDFS-11576) | Block recovery will fail indefinitely if recovery time \> heartbeat interval |  Critical | datanode, hdfs, namenode | Lukas Majercak | Lukas Majercak |
+| [YARN-7607](https://issues.apache.org/jira/browse/YARN-7607) | Remove the trailing duplicated timestamp in container diagnostics message |  Minor | nodemanager | Weiwei Yang | Weiwei Yang |
+| [HADOOP-15080](https://issues.apache.org/jira/browse/HADOOP-15080) | Aliyun OSS: update oss sdk from 2.8.1 to 2.8.3 to remove its dependency on Cat-x "json-lib" |  Blocker | fs/oss | Chris Douglas | SammiChen |
+| [YARN-7591](https://issues.apache.org/jira/browse/YARN-7591) | NPE in async-scheduling mode of CapacityScheduler |  Critical | capacityscheduler | Tao Yang | Tao Yang |
+| [YARN-7608](https://issues.apache.org/jira/browse/YARN-7608) | Incorrect sTarget column causing DataTable warning on RM application and scheduler web page |  Major | resourcemanager, webapp | Weiwei Yang | Gergely Novák |
+| [HDFS-12833](https://issues.apache.org/jira/browse/HDFS-12833) | Distcp : Update the usage of delete option for dependency with update and overwrite option |  Minor | distcp, hdfs | Harshakiran Reddy | usharani |
+| [YARN-7647](https://issues.apache.org/jira/browse/YARN-7647) | NM print inappropriate error log when node-labels is enabled |  Minor | . | Yang Wang | Yang Wang |
+| [HDFS-12907](https://issues.apache.org/jira/browse/HDFS-12907) | Allow read-only access to reserved raw for non-superusers |  Major | namenode | Daryn Sharp | Rushabh S Shah |
+| [HDFS-12881](https://issues.apache.org/jira/browse/HDFS-12881) | Output streams closed with IOUtils suppressing write errors |  Major | . | Jason Lowe | Ajay Kumar |
+| [YARN-7595](https://issues.apache.org/jira/browse/YARN-7595) | Container launching code suppresses close exceptions after writes |  Major | nodemanager | Jason Lowe | Jim Brennan |
+| [HADOOP-15085](https://issues.apache.org/jira/browse/HADOOP-15085) | Output streams closed with IOUtils suppressing write errors |  Major | . | Jason Lowe | Jim Brennan |
+| [YARN-7661](https://issues.apache.org/jira/browse/YARN-7661) | NodeManager metrics return wrong value after update node resource |  Major | . | Yang Wang | Yang Wang |
+| [HDFS-12347](https://issues.apache.org/jira/browse/HDFS-12347) | TestBalancerRPCDelay#testBalancerRPCDelay fails very frequently |  Critical | test | Xiao Chen | Bharat Viswanadham |
+| [YARN-7542](https://issues.apache.org/jira/browse/YARN-7542) | Fix issue that causes some Running Opportunistic Containers to be recovered as PAUSED |  Major | . | Arun Suresh | Sampada Dehankar |
+| [HADOOP-15143](https://issues.apache.org/jira/browse/HADOOP-15143) | NPE due to Invalid KerberosTicket in UGI |  Major | . | Jitendra Nath Pandey | Mukul Kumar Singh |
+| [YARN-7692](https://issues.apache.org/jira/browse/YARN-7692) | Skip validating priority acls while recovering applications |  Blocker | resourcemanager | Charan Hebri | Sunil G |
+| [MAPREDUCE-7028](https://issues.apache.org/jira/browse/MAPREDUCE-7028) | Concurrent task progress updates causing NPE in Application Master |  Blocker | mr-am | Gergo Repas | Gergo Repas |
+| [YARN-7619](https://issues.apache.org/jira/browse/YARN-7619) | Max AM Resource value in Capacity Scheduler UI has to be refreshed for every user |  Major | capacity scheduler, yarn | Eric Payne | Eric Payne |
+| [YARN-7699](https://issues.apache.org/jira/browse/YARN-7699) | queueUsagePercentage is coming as INF for getApp REST api call |  Major | webapp | Sunil G | Sunil G |
+| [YARN-7508](https://issues.apache.org/jira/browse/YARN-7508) | NPE in FiCaSchedulerApp when debug log enabled in async-scheduling mode |  Major | capacityscheduler | Tao Yang | Tao Yang |
+| [YARN-7663](https://issues.apache.org/jira/browse/YARN-7663) | RMAppImpl:Invalid event: START at KILLED |  Minor | resourcemanager | lujie | lujie |
+| [YARN-6948](https://issues.apache.org/jira/browse/YARN-6948) | Invalid event: ATTEMPT\_ADDED at FINAL\_SAVING |  Minor | yarn | lujie | lujie |
+| [YARN-7735](https://issues.apache.org/jira/browse/YARN-7735) | Fix typo in YARN documentation |  Minor | documentation | Takanobu Asanuma | Takanobu Asanuma |
+| [YARN-7727](https://issues.apache.org/jira/browse/YARN-7727) | Incorrect log levels in few logs with QueuePriorityContainerCandidateSelector |  Minor | yarn | Prabhu Joseph | Prabhu Joseph |
+| [HDFS-11915](https://issues.apache.org/jira/browse/HDFS-11915) | Sync rbw dir on the first hsync() to avoid file lost on power failure |  Critical | . | Kanaka Kumar Avvaru | Vinayakumar B |
+| [HDFS-9049](https://issues.apache.org/jira/browse/HDFS-9049) | Make Datanode Netty reverse proxy port to be configurable |  Major | datanode | Vinayakumar B | Vinayakumar B |
+| [HADOOP-15150](https://issues.apache.org/jira/browse/HADOOP-15150) | in FsShell, UGI params should be overidden through env vars(-D arg) |  Major | . | Brahma Reddy Battula | Brahma Reddy Battula |
+| [HADOOP-15181](https://issues.apache.org/jira/browse/HADOOP-15181) | Typo in SecureMode.md |  Trivial | documentation | Masahiro Tanaka | Masahiro Tanaka |
+| [YARN-7737](https://issues.apache.org/jira/browse/YARN-7737) | prelaunch.err file not found exception on container failure |  Major | . | Jonathan Hung | Keqiu Hu |
+| [HDFS-13063](https://issues.apache.org/jira/browse/HDFS-13063) | Fix the incorrect spelling in HDFSHighAvailabilityWithQJM.md |  Trivial | documentation | Jianfei Jiang | Jianfei Jiang |
+| [YARN-7102](https://issues.apache.org/jira/browse/YARN-7102) | NM heartbeat stuck when responseId overflows MAX\_INT |  Critical | . | Botong Huang | Botong Huang |
+| [HADOOP-15151](https://issues.apache.org/jira/browse/HADOOP-15151) | MapFile.fix creates a wrong index file in case of block-compressed data file. |  Major | common | Grigori Rybkine | Grigori Rybkine |
+| [MAPREDUCE-7020](https://issues.apache.org/jira/browse/MAPREDUCE-7020) | Task timeout in uber mode can crash AM |  Major | mr-am | Akira Ajisaka | Peter Bacsko |
+| [YARN-7698](https://issues.apache.org/jira/browse/YARN-7698) | A misleading variable's name in ApplicationAttemptEventDispatcher |  Minor | resourcemanager | Jinjiang Ling | Jinjiang Ling |
+| [HDFS-13100](https://issues.apache.org/jira/browse/HDFS-13100) | Handle IllegalArgumentException when GETSERVERDEFAULTS is not implemented in webhdfs. |  Critical | hdfs, webhdfs | Yongjun Zhang | Yongjun Zhang |
+| [YARN-6868](https://issues.apache.org/jira/browse/YARN-6868) | Add test scope to certain entries in hadoop-yarn-server-resourcemanager pom.xml |  Major | yarn | Ray Chiang | Ray Chiang |
+| [YARN-7849](https://issues.apache.org/jira/browse/YARN-7849) | TestMiniYarnClusterNodeUtilization#testUpdateNodeUtilization fails due to heartbeat sync error |  Major | test | Jason Lowe | Botong Huang |
+| [YARN-7801](https://issues.apache.org/jira/browse/YARN-7801) | AmFilterInitializer should addFilter after fill all parameters |  Critical | . | Sumana Sathish | Wangda Tan |
+| [YARN-7890](https://issues.apache.org/jira/browse/YARN-7890) | NPE during container relaunch |  Major | . | Billie Rinaldi | Jason Lowe |
+| [HDFS-12935](https://issues.apache.org/jira/browse/HDFS-12935) | Get ambiguous result for DFSAdmin command in HA mode when only one namenode is up |  Major | tools | Jianfei Jiang | Jianfei Jiang |
+| [HDFS-13120](https://issues.apache.org/jira/browse/HDFS-13120) | Snapshot diff could be corrupted after concat |  Major | namenode, snapshots | Xiaoyu Yao | Xiaoyu Yao |
+| [HDFS-10453](https://issues.apache.org/jira/browse/HDFS-10453) | ReplicationMonitor thread could stuck for long time due to the race between replication and delete of same file in a large cluster. |  Major | namenode | He Xiaoqiao | He Xiaoqiao |
+| [HDFS-8693](https://issues.apache.org/jira/browse/HDFS-8693) | refreshNamenodes does not support adding a new standby to a running DN |  Critical | datanode, ha | Jian Fang | Ajith S |
+| [MAPREDUCE-7052](https://issues.apache.org/jira/browse/MAPREDUCE-7052) | TestFixedLengthInputFormat#testFormatCompressedIn is flaky |  Major | client, test | Peter Bacsko | Peter Bacsko |
+| [HDFS-13112](https://issues.apache.org/jira/browse/HDFS-13112) | Token expiration edits may cause log corruption or deadlock |  Critical | namenode | Daryn Sharp | Daryn Sharp |
+| [MAPREDUCE-7053](https://issues.apache.org/jira/browse/MAPREDUCE-7053) | Timed out tasks can fail to produce thread dump |  Major | . | Jason Lowe | Jason Lowe |
+| [HADOOP-15206](https://issues.apache.org/jira/browse/HADOOP-15206) | BZip2 drops and duplicates records when input split size is small |  Major | . | Aki Tanaka | Aki Tanaka |
+| [YARN-7947](https://issues.apache.org/jira/browse/YARN-7947) | Capacity Scheduler intra-queue preemption can NPE for non-schedulable apps |  Major | capacity scheduler, scheduler preemption | Eric Payne | Eric Payne |
+| [YARN-7945](https://issues.apache.org/jira/browse/YARN-7945) | Java Doc error in UnmanagedAMPoolManager for branch-2 |  Major | . | Rohith Sharma K S | Botong Huang |
+| [HADOOP-14903](https://issues.apache.org/jira/browse/HADOOP-14903) | Add json-smart explicitly to pom.xml |  Major | common | Ray Chiang | Ray Chiang |
+| [HDFS-12781](https://issues.apache.org/jira/browse/HDFS-12781) | After Datanode down, In Namenode UI Datanode tab is throwing warning message. |  Major | datanode | Harshakiran Reddy | Brahma Reddy Battula |
+| [HDFS-12070](https://issues.apache.org/jira/browse/HDFS-12070) | Failed block recovery leaves files open indefinitely and at risk for data loss |  Major | . | Daryn Sharp | Kihwal Lee |
+| [HADOOP-15251](https://issues.apache.org/jira/browse/HADOOP-15251) | Backport HADOOP-13514 (surefire upgrade) to branch-2 |  Major | test | Chris Douglas | Chris Douglas |
+| [HADOOP-15275](https://issues.apache.org/jira/browse/HADOOP-15275) | Incorrect javadoc for return type of RetryPolicy#shouldRetry |  Minor | documentation | Nanda kumar | Nanda kumar |
+| [YARN-7511](https://issues.apache.org/jira/browse/YARN-7511) | NPE in ContainerLocalizer when localization failed for running container |  Major | nodemanager | Tao Yang | Tao Yang |
+| [MAPREDUCE-7023](https://issues.apache.org/jira/browse/MAPREDUCE-7023) | TestHadoopArchiveLogs.testCheckFilesAndSeedApps fails on rerun |  Minor | test | Gergely Novák | Gergely Novák |
+| [HADOOP-15283](https://issues.apache.org/jira/browse/HADOOP-15283) | Upgrade from findbugs 3.0.1 to spotbugs 3.1.2 in branch-2 to fix docker image build |  Major | . | Xiao Chen | Akira Ajisaka |
+| [YARN-7736](https://issues.apache.org/jira/browse/YARN-7736) | Fix itemization in YARN federation document |  Minor | documentation | Akira Ajisaka | Sen Zhao |
+| [HDFS-13164](https://issues.apache.org/jira/browse/HDFS-13164) | File not closed if streamer fail with DSQuotaExceededException |  Major | hdfs-client | Xiao Chen | Xiao Chen |
+| [HDFS-13109](https://issues.apache.org/jira/browse/HDFS-13109) | Support fully qualified hdfs path in EZ commands |  Major | hdfs | Hanisha Koneru | Hanisha Koneru |
+| [MAPREDUCE-6930](https://issues.apache.org/jira/browse/MAPREDUCE-6930) | mapreduce.map.cpu.vcores and mapreduce.reduce.cpu.vcores are both present twice in mapred-default.xml |  Major | mrv2 | Daniel Templeton | Sen Zhao |
+| [HDFS-12156](https://issues.apache.org/jira/browse/HDFS-12156) | TestFSImage fails without -Pnative |  Major | test | Akira Ajisaka | Akira Ajisaka |
+| [HADOOP-15308](https://issues.apache.org/jira/browse/HADOOP-15308) | TestConfiguration fails on Windows because of paths |  Major | . | Íñigo Goiri | Xiao Liang |
+| [YARN-7636](https://issues.apache.org/jira/browse/YARN-7636) | Re-reservation count may overflow when cluster resource exhausted for a long time |  Major | capacityscheduler | Tao Yang | Tao Yang |
+| [HDFS-12886](https://issues.apache.org/jira/browse/HDFS-12886) | Ignore minReplication for block recovery |  Major | hdfs, namenode | Lukas Majercak | Lukas Majercak |
+| [HDFS-13296](https://issues.apache.org/jira/browse/HDFS-13296) | GenericTestUtils generates paths with drive letter in Windows and fail webhdfs related test cases |  Major | . | Xiao Liang | Xiao Liang |
+| [HDFS-13268](https://issues.apache.org/jira/browse/HDFS-13268) | TestWebHdfsFileContextMainOperations fails on Windows |  Major | . | Íñigo Goiri | Xiao Liang |
+| [YARN-8054](https://issues.apache.org/jira/browse/YARN-8054) | Improve robustness of the LocalDirsHandlerService MonitoringTimerTask thread |  Major | . | Jonathan Eagles | Jonathan Eagles |
+| [YARN-7873](https://issues.apache.org/jira/browse/YARN-7873) | Revert YARN-6078 |  Blocker | . | Billie Rinaldi | Billie Rinaldi |
+| [HDFS-13195](https://issues.apache.org/jira/browse/HDFS-13195) | DataNode conf page  cannot display the current value after reconfig |  Minor | datanode | maobaolong | maobaolong |
+| [HADOOP-15320](https://issues.apache.org/jira/browse/HADOOP-15320) | Remove customized getFileBlockLocations for hadoop-azure and hadoop-azure-datalake |  Major | fs/adl, fs/azure | shanyu zhao | shanyu zhao |
+| [HADOOP-12862](https://issues.apache.org/jira/browse/HADOOP-12862) | LDAP Group Mapping over SSL can not specify trust store |  Major | . | Wei-Chiu Chuang | Wei-Chiu Chuang |
+| [HDFS-13427](https://issues.apache.org/jira/browse/HDFS-13427) | Fix the section titles of transparent encryption document |  Minor | documentation | Akira Ajisaka | Akira Ajisaka |
+
+
+### TESTS:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-14696](https://issues.apache.org/jira/browse/HADOOP-14696) | parallel tests don't work for Windows |  Minor | test | Allen Wittenauer | Allen Wittenauer |
+
+
+### SUB-TASKS:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-13481](https://issues.apache.org/jira/browse/HADOOP-13481) | User end documents for Aliyun OSS FileSystem |  Minor | fs, fs/oss | Genmao Yu | Genmao Yu |
+| [HADOOP-13591](https://issues.apache.org/jira/browse/HADOOP-13591) | Unit test failure in TestOSSContractGetFileStatus and TestOSSContractRootDir |  Major | fs, fs/oss | Genmao Yu | Genmao Yu |
+| [HADOOP-13624](https://issues.apache.org/jira/browse/HADOOP-13624) | Rename TestAliyunOSSContractDispCp |  Major | fs, fs/oss | Kai Zheng | Genmao Yu |
+| [HADOOP-14065](https://issues.apache.org/jira/browse/HADOOP-14065) | AliyunOSS: oss directory filestatus should use meta time |  Major | fs/oss | Fei Hui | Fei Hui |
+| [HADOOP-13768](https://issues.apache.org/jira/browse/HADOOP-13768) | AliyunOSS: handle the failure in the batch delete operation `deleteDirs`. |  Major | fs | Genmao Yu | Genmao Yu |
+| [HADOOP-14069](https://issues.apache.org/jira/browse/HADOOP-14069) | AliyunOSS: listStatus returns wrong file info |  Major | fs/oss | Fei Hui | Fei Hui |
+| [HADOOP-13769](https://issues.apache.org/jira/browse/HADOOP-13769) | AliyunOSS: update oss sdk version |  Major | fs, fs/oss | Genmao Yu | Genmao Yu |
+| [HADOOP-14072](https://issues.apache.org/jira/browse/HADOOP-14072) | AliyunOSS: Failed to read from stream when seek beyond the download size |  Major | fs/oss | Genmao Yu | Genmao Yu |
+| [HADOOP-14192](https://issues.apache.org/jira/browse/HADOOP-14192) | Aliyun OSS FileSystem contract test should implement getTestBaseDir() |  Major | fs/oss | Mingliang Liu | Mingliang Liu |
+| [HADOOP-14194](https://issues.apache.org/jira/browse/HADOOP-14194) | Aliyun OSS should not use empty endpoint as default |  Major | fs/oss | Mingliang Liu | Genmao Yu |
+| [HADOOP-14787](https://issues.apache.org/jira/browse/HADOOP-14787) | AliyunOSS: Implement the `createNonRecursive` operator |  Major | fs, fs/oss | Genmao Yu | Genmao Yu |
+| [HADOOP-14649](https://issues.apache.org/jira/browse/HADOOP-14649) | Update aliyun-sdk-oss version to 2.8.1 |  Major | fs/oss | Ray Chiang | Genmao Yu |
+| [HADOOP-14799](https://issues.apache.org/jira/browse/HADOOP-14799) | Update nimbus-jose-jwt to 4.41.1 |  Major | . | Ray Chiang | Ray Chiang |
+| [HADOOP-14997](https://issues.apache.org/jira/browse/HADOOP-14997) |  Add hadoop-aliyun as dependency of hadoop-cloud-storage |  Minor | fs/oss | Genmao Yu | Genmao Yu |
+| [HDFS-12801](https://issues.apache.org/jira/browse/HDFS-12801) | RBF: Set MountTableResolver as default file resolver |  Minor | . | Íñigo Goiri | Íñigo Goiri |
+| [YARN-7430](https://issues.apache.org/jira/browse/YARN-7430) | Enable user re-mapping for Docker containers by default |  Blocker | security, yarn | Eric Yang | Eric Yang |
+| [YARN-6128](https://issues.apache.org/jira/browse/YARN-6128) | Add support for AMRMProxy HA |  Major | amrmproxy, nodemanager | Subru Krishnan | Botong Huang |
+| [HADOOP-15024](https://issues.apache.org/jira/browse/HADOOP-15024) | AliyunOSS: support user agent configuration and include that & Hadoop version information to oss server |  Major | fs, fs/oss | SammiChen | SammiChen |
+| [HDFS-12858](https://issues.apache.org/jira/browse/HDFS-12858) | RBF: Add router admin commands usage in HDFS commands reference doc |  Minor | documentation | Yiqun Lin | Yiqun Lin |
+| [HDFS-12835](https://issues.apache.org/jira/browse/HDFS-12835) | RBF: Fix Javadoc parameter errors |  Minor | . | Wei Yan | Wei Yan |
+| [YARN-7587](https://issues.apache.org/jira/browse/YARN-7587) | Skip dispatching opportunistic containers to nodes whose queue is already full |  Major | . | Weiwei Yang | Weiwei Yang |
+| [HDFS-12396](https://issues.apache.org/jira/browse/HDFS-12396) | Webhdfs file system should get delegation token from kms provider. |  Major | encryption, kms, webhdfs | Rushabh S Shah | Rushabh S Shah |
+| [YARN-6704](https://issues.apache.org/jira/browse/YARN-6704) | Add support for work preserving NM restart when FederationInterceptor is enabled in AMRMProxyService |  Major | . | Botong Huang | Botong Huang |
+| [HDFS-12875](https://issues.apache.org/jira/browse/HDFS-12875) | RBF: Complete logic for -readonly option of dfsrouteradmin add command |  Major | . | Yiqun Lin | Íñigo Goiri |
+| [YARN-7630](https://issues.apache.org/jira/browse/YARN-7630) | Fix AMRMToken rollover handling in AMRMProxy |  Minor | . | Botong Huang | Botong Huang |
+| [HDFS-12937](https://issues.apache.org/jira/browse/HDFS-12937) | RBF: Add more unit tests for router admin commands |  Major | test | Yiqun Lin | Yiqun Lin |
+| [HDFS-12988](https://issues.apache.org/jira/browse/HDFS-12988) | RBF: Mount table entries not properly updated in the local cache |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HADOOP-15156](https://issues.apache.org/jira/browse/HADOOP-15156) | backport HADOOP-15086 rename fix to branch-2 |  Major | fs/azure | Thomas Marquardt | Thomas Marquardt |
+| [YARN-7716](https://issues.apache.org/jira/browse/YARN-7716) | metricsTimeStart and metricsTimeEnd should be all lower case in the doc |  Major | timelinereader | Haibo Chen | Haibo Chen |
+| [HDFS-12802](https://issues.apache.org/jira/browse/HDFS-12802) | RBF: Control MountTableResolver cache size |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HADOOP-15027](https://issues.apache.org/jira/browse/HADOOP-15027) | AliyunOSS: Support multi-thread pre-read to improve sequential read from Hadoop to Aliyun OSS performance |  Major | fs/oss | wujinhu | wujinhu |
+| [HDFS-13028](https://issues.apache.org/jira/browse/HDFS-13028) | RBF: Fix spurious TestRouterRpc#testProxyGetStats |  Minor | . | Íñigo Goiri | Íñigo Goiri |
+| [YARN-5094](https://issues.apache.org/jira/browse/YARN-5094) | some YARN container events have timestamp of -1 |  Critical | . | Sangjin Lee | Haibo Chen |
+| [YARN-7782](https://issues.apache.org/jira/browse/YARN-7782) | Enable user re-mapping for Docker containers in yarn-default.xml |  Blocker | security, yarn | Eric Yang | Eric Yang |
+| [HDFS-12772](https://issues.apache.org/jira/browse/HDFS-12772) | RBF: Federation Router State State Store internal API |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13042](https://issues.apache.org/jira/browse/HDFS-13042) | RBF: Heartbeat Router State |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13049](https://issues.apache.org/jira/browse/HDFS-13049) | RBF: Inconsistent Router OPTS config in branch-2 and branch-3 |  Minor | . | Wei Yan | Wei Yan |
+| [HDFS-12574](https://issues.apache.org/jira/browse/HDFS-12574) | Add CryptoInputStream to WebHdfsFileSystem read call. |  Major | encryption, kms, webhdfs | Rushabh S Shah | Rushabh S Shah |
+| [HDFS-13044](https://issues.apache.org/jira/browse/HDFS-13044) | RBF: Add a safe mode for the Router |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13043](https://issues.apache.org/jira/browse/HDFS-13043) | RBF: Expose the state of the Routers in the federation |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13068](https://issues.apache.org/jira/browse/HDFS-13068) | RBF: Add router admin option to manage safe mode |  Major | . | Íñigo Goiri | Yiqun Lin |
+| [HDFS-13119](https://issues.apache.org/jira/browse/HDFS-13119) | RBF: Manage unavailable clusters |  Major | . | Íñigo Goiri | Yiqun Lin |
+| [HDFS-13187](https://issues.apache.org/jira/browse/HDFS-13187) | RBF: Fix Routers information shown in the web UI |  Minor | . | Wei Yan | Wei Yan |
+| [HDFS-13184](https://issues.apache.org/jira/browse/HDFS-13184) | RBF: Improve the unit test TestRouterRPCClientRetries |  Minor | test | Yiqun Lin | Yiqun Lin |
+| [HDFS-13199](https://issues.apache.org/jira/browse/HDFS-13199) | RBF: Fix the hdfs router page missing label icon issue |  Major | federation, hdfs | maobaolong | maobaolong |
+| [HDFS-13214](https://issues.apache.org/jira/browse/HDFS-13214) | RBF: Complete document of Router configuration |  Major | . | Tao Jie | Yiqun Lin |
+| [HDFS-13230](https://issues.apache.org/jira/browse/HDFS-13230) | RBF: ConnectionManager's cleanup task will compare each pool's own active conns with its total conns |  Minor | . | Wei Yan | Chao Sun |
+| [HDFS-13233](https://issues.apache.org/jira/browse/HDFS-13233) | RBF: MountTableResolver doesn't return the correct mount point of the given path |  Major | hdfs | wangzhiyuan | wangzhiyuan |
+| [HDFS-13212](https://issues.apache.org/jira/browse/HDFS-13212) | RBF: Fix router location cache issue |  Major | federation, hdfs | Weiwei Wu | Weiwei Wu |
+| [HDFS-13232](https://issues.apache.org/jira/browse/HDFS-13232) | RBF: ConnectionPool should return first usable connection |  Minor | . | Wei Yan | Ekanth S |
+| [HDFS-13240](https://issues.apache.org/jira/browse/HDFS-13240) | RBF: Update some inaccurate document descriptions |  Minor | . | Yiqun Lin | Yiqun Lin |
+| [HDFS-11399](https://issues.apache.org/jira/browse/HDFS-11399) | Many tests fails in Windows due to injecting disk failures |  Major | . | Yiqun Lin | Yiqun Lin |
+| [HDFS-13241](https://issues.apache.org/jira/browse/HDFS-13241) | RBF: TestRouterSafemode failed if the port 8888 is in use |  Major | hdfs, test | maobaolong | maobaolong |
+| [HDFS-13253](https://issues.apache.org/jira/browse/HDFS-13253) | RBF: Quota management incorrect parent-child relationship judgement |  Major | . | Yiqun Lin | Yiqun Lin |
+| [HDFS-13226](https://issues.apache.org/jira/browse/HDFS-13226) | RBF: Throw the exception if mount table entry validated failed |  Major | hdfs | maobaolong | maobaolong |
+| [HDFS-12773](https://issues.apache.org/jira/browse/HDFS-12773) | RBF: Improve State Store FS implementation |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13198](https://issues.apache.org/jira/browse/HDFS-13198) | RBF: RouterHeartbeatService throws out CachedStateStore related exceptions when starting router |  Minor | . | Wei Yan | Wei Yan |
+| [HDFS-13224](https://issues.apache.org/jira/browse/HDFS-13224) | RBF: Resolvers to support mount points across multiple subclusters |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HADOOP-15262](https://issues.apache.org/jira/browse/HADOOP-15262) | AliyunOSS: move files under a directory in parallel when rename a directory |  Major | fs/oss | wujinhu | wujinhu |
+| [HDFS-13215](https://issues.apache.org/jira/browse/HDFS-13215) | RBF: Move Router to its own module |  Major | . | Íñigo Goiri | Wei Yan |
+| [HDFS-13250](https://issues.apache.org/jira/browse/HDFS-13250) | RBF: Router to manage requests across multiple subclusters |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13318](https://issues.apache.org/jira/browse/HDFS-13318) | RBF: Fix FindBugs in hadoop-hdfs-rbf |  Minor | . | Íñigo Goiri | Ekanth S |
+| [HDFS-12792](https://issues.apache.org/jira/browse/HDFS-12792) | RBF: Test Router-based federation using HDFSContract |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-12512](https://issues.apache.org/jira/browse/HDFS-12512) | RBF: Add WebHDFS |  Major | fs | Íñigo Goiri | Wei Yan |
+| [HDFS-13291](https://issues.apache.org/jira/browse/HDFS-13291) | RBF: Implement available space based OrderResolver |  Major | . | Yiqun Lin | Yiqun Lin |
+| [HDFS-13204](https://issues.apache.org/jira/browse/HDFS-13204) | RBF: Optimize name service safe mode icon |  Minor | . | liuhongtong | liuhongtong |
+| [HDFS-13352](https://issues.apache.org/jira/browse/HDFS-13352) | RBF: Add xsl stylesheet for hdfs-rbf-default.xml |  Major | documentation | Takanobu Asanuma | Takanobu Asanuma |
+| [YARN-8010](https://issues.apache.org/jira/browse/YARN-8010) | Add config in FederationRMFailoverProxy to not bypass facade cache when failing over |  Minor | . | Botong Huang | Botong Huang |
+| [HDFS-13347](https://issues.apache.org/jira/browse/HDFS-13347) | RBF: Cache datanode reports |  Minor | . | Íñigo Goiri | Íñigo Goiri |
+| [HDFS-13289](https://issues.apache.org/jira/browse/HDFS-13289) | RBF: TestConnectionManager#testCleanup() test case need correction |  Minor | . | Dibyendu Karmakar | Dibyendu Karmakar |
+| [HDFS-13364](https://issues.apache.org/jira/browse/HDFS-13364) | RBF: Support NamenodeProtocol in the Router |  Major | . | Íñigo Goiri | Íñigo Goiri |
+| [HADOOP-14651](https://issues.apache.org/jira/browse/HADOOP-14651) | Update okhttp version to 2.7.5 |  Major | fs/adl | Ray Chiang | Ray Chiang |
+| [HADOOP-14999](https://issues.apache.org/jira/browse/HADOOP-14999) | AliyunOSS: provide one asynchronous multi-part based uploading mechanism |  Major | fs/oss | Genmao Yu | Genmao Yu |
+
+
+### OTHER:
+
+| JIRA | Summary | Priority | Component | Reporter | Contributor |
+|:---- |:---- | :--- |:---- |:---- |:---- |
+| [HADOOP-15149](https://issues.apache.org/jira/browse/HADOOP-15149) | CryptoOutputStream should implement StreamCapabilities |  Major | fs | Mike Drob | Xiao Chen |
+| [YARN-7691](https://issues.apache.org/jira/browse/YARN-7691) | Add Unit Tests for ContainersLauncher |  Major | . | Sampada Dehankar | Sampada Dehankar |
+| [HADOOP-15177](https://issues.apache.org/jira/browse/HADOOP-15177) | Update the release year to 2018 |  Blocker | build | Akira Ajisaka | Bharat Viswanadham |
+
+
diff --git a/hadoop-common-project/hadoop-common/src/site/markdown/release/2.9.1/RELEASENOTES.2.9.1.md b/hadoop-common-project/hadoop-common/src/site/markdown/release/2.9.1/RELEASENOTES.2.9.1.md
new file mode 100644
index 0000000000..bed70b14e1
--- /dev/null
+++ b/hadoop-common-project/hadoop-common/src/site/markdown/release/2.9.1/RELEASENOTES.2.9.1.md
@@ -0,0 +1,88 @@
+
+<!---
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+-->
+# "Apache Hadoop"  2.9.1 Release Notes
+
+These release notes cover new developer and user-facing incompatibilities, important issues, features, and major improvements.
+
+
+---
+
+* [HADOOP-12756](https://issues.apache.org/jira/browse/HADOOP-12756) | *Major* | **Incorporate Aliyun OSS file system implementation**
+
+Aliyun OSS is widely used among China’s cloud users and this work implemented a new Hadoop compatible filesystem AliyunOSSFileSystem with oss scheme, similar to the s3a and azure support.
+
+
+---
+
+* [HADOOP-14964](https://issues.apache.org/jira/browse/HADOOP-14964) | *Major* | **AliyunOSS: backport Aliyun OSS module to branch-2**
+
+Aliyun OSS is widely used among China’s cloud users and this work implemented a new Hadoop compatible filesystem AliyunOSSFileSystem with oss:// scheme, similar to the s3a and azure support.
+
+
+---
+
+* [HDFS-12883](https://issues.apache.org/jira/browse/HDFS-12883) | *Major* | **RBF: Document Router and State Store metrics**
+
+This JIRA makes following change:
+Change Router metrics context from 'router' to 'dfs'.
+
+
+---
+
+* [HDFS-12895](https://issues.apache.org/jira/browse/HDFS-12895) | *Major* | **RBF: Add ACL support for mount table**
+
+Mount tables support ACL, The users won't be able to modify their own entries (we are assuming these old (no-permissions before) mount table with owner:superuser, group:supergroup, permission:755 as the default permissions).  The fix way is login as superuser to modify these mount table entries.
+
+
+---
+
+* [YARN-7190](https://issues.apache.org/jira/browse/YARN-7190) | *Major* | **Ensure only NM classpath in 2.x gets TSv2 related hbase jars, not the user classpath**
+
+Ensure only NM classpath in 2.x gets TSv2 related hbase jars, not the user classpath.
+
+
+---
+
+* [HADOOP-15156](https://issues.apache.org/jira/browse/HADOOP-15156) | *Major* | **backport HADOOP-15086 rename fix to branch-2**
+
+[WASB] Fix Azure implementation of Filesystem.rename to ensure that at most one operation succeeds when there are multiple, concurrent rename operations targeting the same destination file.
+
+
+---
+
+* [HADOOP-15027](https://issues.apache.org/jira/browse/HADOOP-15027) | *Major* | **AliyunOSS: Support multi-thread pre-read to improve sequential read from Hadoop to Aliyun OSS performance**
+
+Support multi-thread pre-read in AliyunOSSInputStream to improve the sequential read performance from Hadoop to Aliyun OSS.
+
+
+---
+
+* [HDFS-13083](https://issues.apache.org/jira/browse/HDFS-13083) | *Major* | **RBF: Fix doc error setting up client**
+
+Fix the document error of setting up HFDS Router Federation
+
+
+---
+
+* [HDFS-13099](https://issues.apache.org/jira/browse/HDFS-13099) | *Minor* | **RBF: Use the ZooKeeper as the default State Store**
+
+Change default State Store from local file to ZooKeeper. This will require additional zk address to be configured.
+
+
+