[
https://issues.apache.org/jira/browse/HDFS-1508?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12968874#action_12968874
]
Konstantin Shvachko commented on HDFS-1508:
-------------------------------------------
D> It is better not to wait for the next half hour to replace the spare-tire.
You don't need to wait the next half hour. Just restart SNN and the
checkpointing begins. saveNamespace assumes manual; intervention so is
restarting of SNN.
H> But saveNamespace holds the fsnamesystem write lock and changes the image
signature.
This only argues that if saveNamespace() succeeds the simultaneous checkpoint
will be aborted. What is needed is a comprehensive analysis of failure
scenarios.
But it seems easier just to restart SNN.
> Ability to do savenamespace without being in safemode
> -----------------------------------------------------
>
> Key: HDFS-1508
> URL: https://issues.apache.org/jira/browse/HDFS-1508
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: name-node
> Reporter: dhruba borthakur
> Assignee: dhruba borthakur
> Attachments: savenamespaceWithoutSafemode.txt,
> savenamespaceWithoutSafemode2.txt, savenamespaceWithoutSafemode3.txt
>
>
> In the current code, the administrator can run savenamespace only after
> putting the namenode in safemode. This means that applications that are
> writing to HDFS encounters errors because the NN is in safemode. We would
> like to allow saveNamespace even when the namenode is not in safemode.
> The savenamespace command already acquires the FSNamesystem writelock. There
> is no need to require that the namenode is in safemode too.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
