[
https://issues.apache.org/jira/browse/HDFS-10659?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15412105#comment-15412105
]
Hanisha Koneru commented on HDFS-10659:
---------------------------------------
Thank you [~jingzhao] for the guidance.
> Namenode crashes after Journalnode re-installation in an HA cluster due to
> missing paxos directory
> --------------------------------------------------------------------------------------------------
>
> Key: HDFS-10659
> URL: https://issues.apache.org/jira/browse/HDFS-10659
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: ha, journal-node
> Affects Versions: 2.7.1
> Reporter: Amit Anand
> Assignee: Hanisha Koneru
> Attachments: HDFS-10659.000.patch
>
>
> In my environment I am seeing {{Namenodes}} crashing down after majority of
> {{Journalnodes}} are re-installed. We manage multiple clusters and do rolling
> upgrades followed by rolling re-install of each node including master(NN, JN,
> RM, ZK) nodes. When a journal node is re-installed or moved to a new
> disk/host, instead of running {{"initializeSharedEdits"}} command, I copy
> {{VERSION}} file from one of the other {{Journalnode}} and that allows my
> {{NN}} to start writing data to the newly installed {{Journalnode}}.
> To acheive quorum for JN and recover unfinalized segments NN during starupt
> creates NNNN.tmp files under {{"<disk>/jn/current/paxos"}} directory . In
> current implementation "paxos" directry is only created during
> {{"initializeSharedEdits"}} command and if a JN is re-installed the "paxos"
> directory is not created upon JN startup or by NN while writing NNNN.tmp
> files which causes NN to crash with following error message:
> {code}
> 192.168.100.16:8485: /disk/1/dfs/jn/Test-Laptop/current/paxos/64044.tmp (No
> such file or directory)
> at java.io.FileOutputStream.open(Native Method)
> at java.io.FileOutputStream.<init>(FileOutputStream.java:221)
> at java.io.FileOutputStream.<init>(FileOutputStream.java:171)
> at
> org.apache.hadoop.hdfs.util.AtomicFileOutputStream.<init>(AtomicFileOutputStream.java:58)
> at
> org.apache.hadoop.hdfs.qjournal.server.Journal.persistPaxosData(Journal.java:971)
> at
> org.apache.hadoop.hdfs.qjournal.server.Journal.acceptRecovery(Journal.java:846)
> at
> org.apache.hadoop.hdfs.qjournal.server.JournalNodeRpcServer.acceptRecovery(JournalNodeRpcServer.java:205)
> at
> org.apache.hadoop.hdfs.qjournal.protocolPB.QJournalProtocolServerSideTranslatorPB.acceptRecovery(QJournalProtocolServerSideTranslatorPB.java:249)
> at
> org.apache.hadoop.hdfs.qjournal.protocol.QJournalProtocolProtos$QJournalProtocolService$2.callBlockingMethod(QJournalProtocolProtos.java:25435)
> at
> org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:616)
> at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:969)
> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2151)
> at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2147)
> at java.security.AccessController.doPrivileged(Native Method)
> at javax.security.auth.Subject.doAs(Subject.java:415)
> at
> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
> at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2145)
> {code}
> The current
> [getPaxosFile|https://github.com/apache/hadoop/blob/trunk/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JNStorage.java#L128-L130]
> method simply returns a path to a file under "paxos" directory without
> verifiying its existence. Since "paxos" directoy holds files that are
> required for NN recovery and acheiving JN quorum my proposed solution is to
> add a check to "getPaxosFile" method and create the {{"paxos"}} directory if
> it is missing.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org
