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https://issues.apache.org/jira/browse/HDFS-250?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Allen Wittenauer resolved HDFS-250.
-----------------------------------

    Resolution: Fixed

This has been fixed a few different ways, most recently with the QJM.

> Save (sync) journal (fsimage) to alternate/secondary/read-only name node
> ------------------------------------------------------------------------
>
>                 Key: HDFS-250
>                 URL: https://issues.apache.org/jira/browse/HDFS-250
>             Project: Hadoop HDFS
>          Issue Type: New Feature
>            Reporter: Robert Chansler
>
> The name node journal records HDFS transactions. The journal can be written 
> to multiple file systems (but not HDFS itself!) to increase the durability of 
> the journal. The transaction has to wait for each copy to sync. If one of the 
> file systems becomes slow, performance of HDFS is affected. 
> As an alternative to directly writing a remote file, the transaction could be 
> written to another name node. The alternate node could be the secondary name 
> node, or a read-only name node replica that provides a journal service. The 
> idea being that receipt of the record--but not its sync to the local 
> disk--would be good enough as a journal replica. This could provide a fast, 
> predictable journal replica where common-mode failures are sufficiently 
> improbable or tolerable.
> (1791249)



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