[
https://issues.apache.org/jira/browse/HDFS-11009?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15583554#comment-15583554
]
Andrew Wang commented on HDFS-11009:
------------------------------------
Thanks for working on this Xiao. Looks good overall, though a few review
comments:
* Looks like both the block and out files are required parameters, so no please
do not use "[]" in the help text and doc. It's also debatable whether these
should be flags at all, since UNIX normally uses positional args if they're
required.
* I'm mixed on this one, but it'd be more clear if this command was named
"computeMeta". Unfortunately there's also the existing "verify" command, and
the commands are named "*BlockChecksumCommand". The debug command comes with no
compat guarantees, so maybe we do some renames even for branch-2.
* It'd also be nice to add some disclaimers to the doc/help text. I'm guessing
this is meant for use in emergency situations where the block only has corrupt
replicas? I'm also wondering about the danger of divergent state on different
DNs, since I don't think HDFS-level mechanisms like the BlockScanner or FBRs
will catch this.
> Add a tool to reconstruct block meta file from CLI
> --------------------------------------------------
>
> Key: HDFS-11009
> URL: https://issues.apache.org/jira/browse/HDFS-11009
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: datanode
> Reporter: Xiao Chen
> Assignee: Xiao Chen
> Attachments: HDFS-11009.01.patch, HDFS-11009.02.patch
>
>
> If the block file on local disk presents, but the meta file is missing, it's
> theoretically possible to manually restore the meta file and have the block
> readable.
> This jira is to propose to add such a tool to do that.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
