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: [email protected]
For additional commands, e-mail: [email protected]
