hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Bikas Saha (Commented) (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-3092) Enable journal protocol based editlog streaming for standby namenode
Date Thu, 12 Apr 2012 22:01:23 GMT

    [ https://issues.apache.org/jira/browse/HDFS-3092?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13252895#comment-13252895
] 

Bikas Saha commented on HDFS-3092:
----------------------------------

Todd, I was going to post this same comment on HDFS-3077 because I did not see 2 phase commits
mentioned there either even though the initial comments mentioned implementing ZAB. The doc
did mention standby node tailing as a requirement but it wasn't clear how this is being achieved
in the absence of a coordinated distributed commit.

bq. That's my plan in HDFS-3077, and in fact that's the current behavior of the SBN, even
when operating on NFS.
Hari updated me offline that standby NN currently tails only the finalized edits. So this
works fine. By 'my plan' are you referring to an API on the journal node to read latest edits
that replaces the current standby NN tailing code?
                
> Enable journal protocol based editlog streaming for standby namenode
> --------------------------------------------------------------------
>
>                 Key: HDFS-3092
>                 URL: https://issues.apache.org/jira/browse/HDFS-3092
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: ha, name-node
>    Affects Versions: 0.24.0, 0.23.3
>            Reporter: Suresh Srinivas
>            Assignee: Suresh Srinivas
>         Attachments: MultipleSharedJournals.pdf, MultipleSharedJournals.pdf, MultipleSharedJournals.pdf
>
>
> Currently standby namenode relies on reading shared editlogs to stay current with the
active namenode, for namespace changes. BackupNode used streaming edits from active namenode
for doing the same. This jira is to explore using journal protocol based editlog streams for
the standby namenode. A daemon in standby will get the editlogs from the active and write
it to local edits. To begin with, the existing standby mechanism of reading from a file, will
continue to be used, instead of from shared edits, from the local edits.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message