[
https://issues.apache.org/jira/browse/HDFS-1103?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12867606#action_12867606
]
Hairong Kuang commented on HDFS-1103:
-------------------------------------
In the 0.21 append design, if every BlockReceiver could make sure that its
buffered packet gets flushed to the disk before it exits on error, then I do
not think the problem you described will happen. Probably the code does not
enforce it now. I do not think that we should use the max of RBWs. In 0.21,
there is no concept of validate length for RBWs.
> Replica recovery doesn't distinguish between flushed-but-corrupted last chunk
> and unflushed last chunk
> ------------------------------------------------------------------------------------------------------
>
> Key: HDFS-1103
> URL: https://issues.apache.org/jira/browse/HDFS-1103
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: data-node
> Affects Versions: 0.21.0, 0.22.0
> Reporter: Todd Lipcon
> Priority: Blocker
> Attachments: hdfs-1103-test.txt
>
>
> When the DN creates a replica under recovery, it calls validateIntegrity,
> which truncates the last checksum chunk off of a replica if it is found to be
> invalid. Then when the block recovery process happens, this shortened block
> wins over a longer replica from another node where there was no corruption.
> Thus, if just one of the DNs has an invalid last checksum chunk, data that
> has been sync()ed to other datanodes can be lost.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
