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https://issues.apache.org/jira/browse/RANGER-1501?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15963809#comment-15963809
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Ramesh Mani commented on RANGER-1501:
-------------------------------------
AuditHandler has the JVMHook registered with Hadoop's ShutdownHookManager and
it does a cleaup which waits and closes all the Audit destination. the
HDFSAuditDestination.stop() also does the flush() and close() when NN goes
done. So where did you see the data loss, what is the scenario under which you
see it?
> Audit Flush to HDFS does not actually cause the audit logs to be flushed to
> HDFS
> ---------------------------------------------------------------------------------
>
> Key: RANGER-1501
> URL: https://issues.apache.org/jira/browse/RANGER-1501
> Project: Ranger
> Issue Type: Bug
> Components: audit
> Affects Versions: 0.7.0
> Reporter: Yan
> Assignee: Yan
> Fix For: master
>
> Attachments:
> 0001-RANGER-1501-Audit-Flush-to-HDFS-does-not-actually-ca.patch
>
>
> The reason is that HDFS file stream's flush() call does not really flush the
> data all the way to disk, nor even makes the data visible to HDFS users. See
> the HDFS semantics of the flush/sync at
> https://issues.apache.org/jira/browse/HADOOP-6313.
> Consequently the audit logs on HDFS won't be visible/durable from HDFS client
> until the log file is closed. This will, among other issues, boost chances of
> losing audit logs in case of system failure.
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