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https://issues.apache.org/jira/browse/HDFS-3092?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13244416#comment-13244416
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Suresh Srinivas commented on HDFS-3092:
---------------------------------------

bq. Yes, that solves the problem, but then requires that the recovery protocol 
open up and read the edits out of the logs. It also leaks the edits storage 
mechanism into the edits contents, so I don't think it's quite the right design.
Given the reliance on rolling, three pieces of information is needed per JD. 
Last txid, the segment start txid and associated information.

bq. The thing is, once you've implemented all of this, I don't think your 
solution is any less complex than the one in HDFS-3077 
May be. But I am not sure I know what you are doing in HDFS-3077. At least you 
know the details of what is being done here :-)
                
> 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
>
>
> 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.

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