hadoop-mapreduce-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Daryn Sharp (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (MAPREDUCE-2764) Fix renewal of dfs delegation tokens
Date Thu, 04 Aug 2011 23:44:27 GMT

    [ https://issues.apache.org/jira/browse/MAPREDUCE-2764?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13079681#comment-13079681

Daryn Sharp commented on MAPREDUCE-2764:

The changes aren't entirely independent so I'm not sure if I can easily tease them apart,
but I'll start trying to break it up into more jiras...  The token selectors were all just
copy-n-paste, so I would have been further perpetrating unnecessary duplication if I didn't
commonize them.  The {{HftpFileSystem}} changes were the fulcrum of this bug.

To help clarify the approach I took in case there is misunderstanding: I let the "service"
be one of two formats: "scheme://authority" or "authority" (for compatibility).  I added {{getServiceAuthority}}
in order to easily get the authority irregardless of the format.  The benefits to supporting
both formats in the same field is to avoid unnecessary duplication of the same data, and more
importantly to avoid introducing binary incompatibility to the tokens.  Unless I'm mistaken,
your recommendation for a new issuer field would have those downsides.  Are there other benefits
that would outweigh those issues?

> Fix renewal of dfs delegation tokens
> ------------------------------------
>                 Key: MAPREDUCE-2764
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-2764
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>            Reporter: Daryn Sharp
>            Assignee: Daryn Sharp
>             Fix For:
>         Attachments: MAPREDUCE-2764.patch
> The JT may have issues renewing hftp tokens which disrupt long distcp jobs.  The problem
is the JT's delegation token renewal code is built on brittle assumptions.  The token's service
field contains only the "ip:port" pair.  The renewal process assumes that the scheme must
be hdfs.  If that fails due to a {{VersionMismatchException}}, it tries https based on another
assumption that it must be hftp if it's not hdfs.  A number of other exceptions, most commonly
{{IOExceptions}}, can be generated which fouls up the renewal since it won't fallback to https.

This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message