| YARN-1883 | TestRMAdminService fails due to inconsistent entries in UserGroups | Major | . | Mit Desai | Mit Desai | 
| HADOOP-10455 | When there is an exception, ipc.Server should first check whether it is an terse exception | Major | ipc | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze | 
| MAPREDUCE-5818 | hsadmin cmd is missing in mapred.cmd | Major | . | Jian He | Jian He | 
| HADOOP-10456 | Bug in Configuration.java exposed by Spark (ConcurrentModificationException) | Major | conf | Nishkam Ravi | Nishkam Ravi | 
| YARN-1837 | TestMoveApplication.testMoveRejectedByScheduler randomly fails | Major | . | Tsuyoshi Ozawa | Hong Zhiguo | 
| HDFS-6197 | Rolling upgrade rollback on Windows can fail attempting to rename edit log segment files to a destination that already exists. | Minor | namenode | Chris Nauroth | Chris Nauroth | 
| HDFS-6198 | DataNode rolling upgrade does not correctly identify current block pool directory and replace with trash on Windows. | Major | datanode | Chris Nauroth | Chris Nauroth | 
| YARN-1908 | Distributed shell with custom script has permission error. | Major | applications/distributed-shell | Tassapol Athiapinya | Vinod Kumar Vavilapalli | 
| YARN-1907 | TestRMApplicationHistoryWriter#testRMWritingMassiveHistory runs slow and intermittently fails | Major | . | Mit Desai | Mit Desai | 
| HDFS-6215 | Wrong error message for upgrade | Minor | . | Kihwal Lee | Kihwal Lee | 
| HADOOP-10473 | TestCallQueueManager is still flaky | Minor | test | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze | 
| HDFS-6206 | DFSUtil.substituteForWildcardAddress may throw NPE | Major | . | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze | 
| HDFS-6204 | TestRBWBlockInvalidation may fail | Minor | test | Tsz Wo Nicholas Sze | Tsz Wo Nicholas Sze | 
| HDFS-6209 | Fix flaky test TestValidateConfigurationSettings.testThatDifferentRPCandHttpPortsAreOK | Minor | test | Arpit Agarwal | Arpit Agarwal | 
| HDFS-6208 | DataNode caching can leak file descriptors. | Major | datanode | Chris Nauroth | Chris Nauroth | 
| YARN-1910 | TestAMRMTokens fails on windows | Major | . | Xuan Gong | Xuan Gong | 
| MAPREDUCE-5824 | TestPipesNonJavaInputFormat.testFormat fails in windows | Major | . | Xuan Gong | Xuan Gong | 
| YARN-1920 | TestFileSystemApplicationHistoryStore.testMissingApplicationAttemptHistoryData fails in windows | Major | . | Vinod Kumar Vavilapalli | Vinod Kumar Vavilapalli | 
| YARN-1914 | Test TestFSDownload.testDownloadPublicWithStatCache fails on Windows | Major | . | Varun Vasudev | Varun Vasudev | 
| YARN-1903 | Killing Container on NEW and LOCALIZING will result in exitCode and diagnostics not set | Major | . | Zhijie Shen | Zhijie Shen | 
| YARN-1924 | STATE_STORE_OP_FAILED happens when ZKRMStateStore tries to update app(attempt) before storing it | Critical | . | Arpit Gupta | Jian He | 
| MAPREDUCE-5815 | Fix NPE in TestMRAppMaster | Blocker | client, mrv2 | Gera Shegalov | Akira Ajisaka | 
| YARN-1926 | DistributedShell unit tests fail on Windows | Major | . | Varun Vasudev | Varun Vasudev | 
| HDFS-6231 | DFSClient hangs infinitely if using hedged reads and all eligible datanodes die. | Major | hdfs-client | Chris Nauroth | Chris Nauroth | 
| MAPREDUCE-5826 | TestHistoryServerFileSystemStateStoreService.testTokenStore fails in windows | Major | . | Varun Vasudev | Varun Vasudev | 
| HADOOP-10490 | TestMapFile and TestBloomMapFile leak file descriptors. | Minor | test | Chris Nauroth | Chris Nauroth | 
| HDFS-6234 | TestDatanodeConfig#testMemlockLimit fails on Windows due to invalid file path. | Trivial | datanode, test | Chris Nauroth | Chris Nauroth | 
| HADOOP-8826 | Docs still refer to 0.20.205 as stable line | Minor | . | Robert Joseph Evans | Mit Desai | 
| HDFS-6235 | TestFileJournalManager can fail on Windows due to file locking if tests run out of order. | Trivial | namenode, test | Chris Nauroth | Chris Nauroth | 
| HDFS-6229 | Race condition in failover can cause RetryCache fail to work | Major | ha | Jing Zhao | Jing Zhao | 
| HDFS-6232 | OfflineEditsViewer throws a NPE on edits containing ACL modifications | Major | tools | Stephen Chu | Akira Ajisaka | 
| HDFS-6236 | ImageServlet should use Time#monotonicNow to measure latency. | Minor | namenode | Chris Nauroth | Chris Nauroth | 
| MAPREDUCE-5828 | TestMapReduceJobControl fails on JDK 7 + Windows | Major | . | Vinod Kumar Vavilapalli | Vinod Kumar Vavilapalli | 
| YARN-1933 | TestAMRestart and TestNodeHealthService failing sometimes on Windows | Major | . | Jian He | Jian He | 
| YARN-1928 | TestAMRMRPCNodeUpdates fails ocassionally | Major | . | Zhijie Shen | Zhijie Shen | 
| YARN-1934 | Potential NPE in ZKRMStateStore caused by handling Disconnected event from ZK. | Blocker | resourcemanager | Rohith Sharma K S | Karthik Kambatla | 
| MAPREDUCE-3191 | docs for map output compression incorrectly reference SequenceFile | Trivial | . | Todd Lipcon | Chen He | 
| YARN-1931 | Private API change in YARN-1824 in 2.4 broke compatibility with previous releases | Blocker | applications | Thomas Graves | Sandy Ryza | 
| YARN-1932 | Javascript injection on the job status page | Blocker | . | Mit Desai | Mit Desai | 
| HDFS-6245 | datanode fails to start with a bad disk even when failed volumes is set | Major | . | Arpit Gupta | Arpit Agarwal | 
| HADOOP-10522 | JniBasedUnixGroupMapping mishandles errors | Critical | . | Kihwal Lee | Kihwal Lee | 
| MAPREDUCE-5827 | TestSpeculativeExecutionWithMRApp fails | Major | . | Zhijie Shen | Zhijie Shen | 
| MAPREDUCE-5832 | Few tests in TestJobClient fail on Windows | Major | . | Jian He | Vinod Kumar Vavilapalli | 
| HADOOP-10527 | Fix incorrect return code and allow more retries on EINTR | Major | . | Kihwal Lee | Kihwal Lee | 
| MAPREDUCE-5841 | uber job doesn’t terminate on getting mapred job kill | Major | mrv2 | Sangjin Lee | Sangjin Lee | 
| YARN-1975 | Used resources shows escaped html in CapacityScheduler and FairScheduler page | Major | resourcemanager | Nathan Roberts | Mit Desai | 
| MAPREDUCE-5835 | Killing Task might cause the job to go to ERROR state | Critical | . | Ming Ma | Ming Ma | 
| MAPREDUCE-5714 | TestMRAppComponentDependencies causes surefire to exit without saying proper goodbye | Major | test | Jinghui Wang | Jinghui Wang | 
| HDFS-2882 | DN continues to start up, even if block pool fails to initialize | Major | datanode | Todd Lipcon | Vinayakumar B | 
| YARN-1929 | DeadLock in RM when automatic failover is enabled. | Blocker | resourcemanager | Rohith Sharma K S | Karthik Kambatla | 
| YARN-1201 | TestAMAuthorization fails with local hostname cannot be resolved | Minor | resourcemanager | Nemon Lou | Wangda Tan | 
| HADOOP-10562 | Namenode exits on exception without printing stack trace in AbstractDelegationTokenSecretManager | Critical | . | Suresh Srinivas | Suresh Srinivas | 
| HDFS-6340 | DN can’t finalize upgrade | Blocker | datanode | Rahul Singhal | Rahul Singhal | 
| HDFS-6329 | WebHdfs does not work if HA is enabled on NN but logical URI is not configured. | Blocker | . | Kihwal Lee | Kihwal Lee | 
| HDFS-6313 | WebHdfs may use the wrong NN when configured for multiple HA NNs | Blocker | webhdfs | Daryn Sharp | Kihwal Lee | 
| YARN-1976 | Tracking url missing http protocol for FAILED application | Major | . | Yesha Vora | Junping Du | 
| YARN-2016 | Yarn getApplicationRequest start time range is not honored | Major | resourcemanager | Venkat Ranganathan | Junping Du | 
| YARN-1986 | In Fifo Scheduler, node heartbeat in between creating app and attempt causes NPE | Critical | . | Jon Bringhurst | Hong Zhiguo | 
| MAPREDUCE-5821 | IFile merge allocates new byte array for every value | Major | performance, task | Todd Lipcon | Todd Lipcon | 
| HDFS-6326 | WebHdfs ACL compatibility is broken | Blocker | webhdfs | Daryn Sharp | Chris Nauroth | 
| HDFS-6361 | TestIdUserGroup.testUserUpdateSetting failed due to out of range nfsnobody Id | Major | nfs | Yongjun Zhang | Yongjun Zhang | 
| HDFS-6362 | InvalidateBlocks is inconsistent in usage of DatanodeUuid and StorageID | Blocker | namenode | Arpit Agarwal | Arpit Agarwal | 
| HDFS-6402 | Suppress findbugs warning for failure to override equals and hashCode in FsAclPermission. | Trivial | namenode | Chris Nauroth | Chris Nauroth | 
| YARN-2066 | Wrong field is referenced in GetApplicationsRequestPBImpl#mergeLocalToBuilder() | Minor | . | Ted Yu | Hong Zhiguo | 
| HDFS-6325 | Append should fail if the last block has insufficient number of replicas | Major | namenode | Konstantin Shvachko | Keith Pak | 
| HDFS-6397 | NN shows inconsistent value in deadnode count | Critical | . | Mohammad Kamrul Islam | Mohammad Kamrul Islam | 
| HADOOP-10612 | NFS failed to refresh the user group id mapping table | Major | nfs | Brandon Li | Brandon Li | 
| YARN-2081 | TestDistributedShell fails after YARN-1962 | Minor | applications/distributed-shell | Hong Zhiguo | Hong Zhiguo | 
| HDFS-6411 | nfs-hdfs-gateway mount raises I/O error and hangs when a unauthorized user attempts to access it | Major | nfs | Zhongyi Xie | Brandon Li | 
| MAPREDUCE-5830 | HostUtil.getTaskLogUrl is not backwards binary compatible with 2.3 | Blocker | . | Jason Lowe | Akira Ajisaka | 
| HADOOP-11273 | TestMiniKdc failure: login options not compatible with IBM JDK | Major | test | Gao Zhong Liang | Gao Zhong Liang |