YCozy created HDFS-15235: ---------------------------- Summary: Transient network failure during NameNode failover makes cluster unavailable Key: HDFS-15235 URL: https://issues.apache.org/jira/browse/HDFS-15235 Project: Hadoop HDFS Issue Type: Bug Affects Versions: 3.3.0 Reporter: YCozy
We have an HA cluster with two NameNodes: an active NN1 and a standby NN2. At some point, NN1 becomes unhealthy and the admin tries to manually failover to NN2 by running command {code:java} $ hfs haadmin -failover NN1 NN2 {code} NN2 receives the request and becomes active: {code:java} 2020-03-24 00:24:56,412 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Stopping services started for standby state 2020-03-24 00:24:56,413 WARN org.apache.hadoop.hdfs.server.namenode.ha.EditLogTailer: Edit log tailer interrupted: sleep interrupted 2020-03-24 00:24:56,415 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Starting services required for active state 2020-03-24 00:24:56,417 INFO org.apache.hadoop.hdfs.server.namenode.FileJournalManager: Recovering unfinalized segments in /app/ha-name-dir-shared/current 2020-03-24 00:24:56,419 INFO org.apache.hadoop.hdfs.server.namenode.FileJournalManager: Recovering unfinalized segments in /app/nn2/name/current 2020-03-24 00:24:56,419 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Catching up to latest edits from old active before taking over writer role in edits logs 2020-03-24 00:24:56,435 INFO org.apache.hadoop.hdfs.server.namenode.FSImage: Reading org.apache.hadoop.hdfs.server.namenode.RedundantEditLogInputStream@7c3095fa expecting start txid #1 2020-03-24 00:24:56,436 INFO org.apache.hadoop.hdfs.server.namenode.FSImage: Start loading edits file /app/ha-name-dir-shared/current/edits_0000000000000000001-0000000000000000019 maxTxnsToRead = 9223372036854775807 2020-03-24 00:24:56,441 INFO org.apache.hadoop.hdfs.server.namenode.RedundantEditLogInputStream: Fast-forwarding stream '/app/ha-name-dir-shared/current/edits_0000000000000000001-0000000000000000019' to transaction ID 1 2020-03-24 00:24:56,567 INFO org.apache.hadoop.hdfs.server.namenode.FSImage: Loaded 1 edits file(s) (the last named /app/ha-name-dir-shared/current/edits_0000000000000000001-0000000000000000019) of total size 1305.0, total edits 19.0, total load time 109.0 ms 2020-03-24 00:24:56,567 INFO org.apache.hadoop.hdfs.server.blockmanagement.DatanodeManager: Marking all datanodes as stale 2020-03-24 00:24:56,568 INFO org.apache.hadoop.hdfs.server.blockmanagement.BlockManager: Processing 4 messages from DataNodes that were previously queued during standby state 2020-03-24 00:24:56,569 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Reprocessing replication and invalidation queues 2020-03-24 00:24:56,569 INFO org.apache.hadoop.hdfs.server.blockmanagement.BlockManager: initializing replication queues 2020-03-24 00:24:56,570 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Will take over writing edit logs at txnid 20 2020-03-24 00:24:56,571 INFO org.apache.hadoop.hdfs.server.namenode.FSEditLog: Starting log segment at 20 2020-03-24 00:24:56,812 INFO org.apache.hadoop.hdfs.server.namenode.FSDirectory: Initializing quota with 4 thread(s) 2020-03-24 00:24:56,819 INFO org.apache.hadoop.hdfs.server.namenode.FSDirectory: Quota initialization completed in 6 millisecondsname space=3storage space=24690storage types=RAM_DISK=0, SSD=0, DISK=0, ARCHIVE=0, PROVIDED=0 2020-03-24 00:24:56,827 INFO org.apache.hadoop.hdfs.server.blockmanagement.CacheReplicationMonitor: Starting CacheReplicationMonitor with interval 30000 milliseconds {code} But NN2 fails to send back the RPC response because of temporary network partitioning. {code:java} java.io.EOFException: End of File Exception between local host is: "24e7b5a52e85/172.17.0.2"; destination host is: "127.0.0.3":8180; : java.io.EOFException; For more details see: http://wiki.apache.org/hadoop/EOFException at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at org.apache.hadoop.net.NetUtils.wrapWithMessage(NetUtils.java:837) at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:791) at org.apache.hadoop.ipc.Client.getRpcResponse(Client.java:1597) at org.apache.hadoop.ipc.Client.call(Client.java:1539) at org.apache.hadoop.ipc.Client.call(Client.java:1436) at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:233) at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:118) at com.sun.proxy.$Proxy8.transitionToActive(Unknown Source) at org.apache.hadoop.ha.protocolPB.HAServiceProtocolClientSideTranslatorPB.transitionToActive(HAServiceProtocolClientSideTranslatorPB.java:101) at org.apache.hadoop.ha.HAServiceProtocolHelper.transitionToActive(HAServiceProtocolHelper.java:48) at org.apache.hadoop.ha.FailoverController.failover(FailoverController.java:226) at org.apache.hadoop.hdfs.tools.DFSHAAdmin.failover(DFSHAAdmin.java:319) at org.apache.hadoop.hdfs.tools.DFSHAAdmin.runCmd(DFSHAAdmin.java:217) at org.apache.hadoop.ha.HAAdmin.run(HAAdmin.java:346) at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76) at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:90) at org.apache.hadoop.hdfs.tools.DFSHAAdmin.main(DFSHAAdmin.java:329) Caused by: java.io.EOFException at java.io.DataInputStream.readInt(DataInputStream.java:392) at org.apache.hadoop.ipc.Client$IpcStreams.readResponse(Client.java:1912) at org.apache.hadoop.ipc.Client$Connection.receiveRpcResponse(Client.java:1222) at org.apache.hadoop.ipc.Client$Connection.run(Client.java:1092){code} {{}} As a result, the haadmin command thinks the failover fails and starts to fence NN2 using SshFenceByTcpPort. Unfortunately, the network partition stops, so the fencing succeeds. As a result, NN2 is killed and the cluster has no health NameNode. {code:java} 2020-03-24 00:24:57,622 INFO ha.SshFenceByTcpPort: Successfully killed process that was listening on port 8180 2020-03-24 00:24:57,623 INFO SshFenceByTcpPort.jsch: Disconnecting from 127.0.0.3 port 22 2020-03-24 00:24:57,627 INFO ha.NodeFencer: ====== Fencing successful by method org.apache.hadoop.ha.SshFenceByTcpPort(null) ======{code} -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-dev-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-dev-h...@hadoop.apache.org