hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Todd Lipcon (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HDFS-988) saveNamespace can corrupt edits log
Date Tue, 08 Jun 2010 20:54:14 GMT

    [ https://issues.apache.org/jira/browse/HDFS-988?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12876798#action_12876798
] 

Todd Lipcon commented on HDFS-988:
----------------------------------

Nicolas: by seqnum you're referring to the generation stamp on the block being written, as
the client continues to initiate recovery during shutdown? Do we also need to pull in HDFS-1145
then? (I have this patch applied on my append branch, but not 1145, and not seen errors, just
seems to make sense)

> saveNamespace can corrupt edits log
> -----------------------------------
>
>                 Key: HDFS-988
>                 URL: https://issues.apache.org/jira/browse/HDFS-988
>             Project: Hadoop HDFS
>          Issue Type: Bug
>          Components: name-node
>    Affects Versions: 0.21.0, 0.22.0, 0.20-append
>            Reporter: dhruba borthakur
>            Assignee: Todd Lipcon
>            Priority: Blocker
>         Attachments: hdfs-988.txt, saveNamespace.txt, saveNamespace_20-append.patch
>
>
> The adminstrator puts the namenode is safemode and then issues the savenamespace command.
This can corrupt the edits log. The problem is that  when the NN enters safemode, there could
still be pending logSycs occuring from other threads. Now, the saveNamespace command, when
executed, would save a edits log with partial writes. I have seen this happen on 0.20.
> https://issues.apache.org/jira/browse/HDFS-909?focusedCommentId=12828853&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12828853

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message