hadoop-hdfs-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Kihwal Lee (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HDFS-11817) A faulty node can cause a lease leak and NPE on accessing data
Date Thu, 18 May 2017 20:30:05 GMT

    [ https://issues.apache.org/jira/browse/HDFS-11817?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16016420#comment-16016420

Kihwal Lee commented on HDFS-11817:

Hi, [~raviprak]. We've seen what you described above. It is not directly related to this jira,
but I think we had an internal fix for this. Just a couple of days ago, we were talking about
pushing the fix to Apache. Please do file a jira and let me know.

> A faulty node can cause a lease leak and NPE on accessing data
> --------------------------------------------------------------
>                 Key: HDFS-11817
>                 URL: https://issues.apache.org/jira/browse/HDFS-11817
>             Project: Hadoop HDFS
>          Issue Type: Bug
>    Affects Versions: 2.8.0
>            Reporter: Kihwal Lee
>            Assignee: Kihwal Lee
>            Priority: Critical
>         Attachments: hdfs-11817_supplement.txt
> When the namenode performs a lease recovery for a failed write, the {{commitBlockSynchronization()}}
will fail, if none of the new target has sent a received-IBR.  At this point, the data is
inaccessible, as the namenode will throw a {{NullPointerException}} upon {{getBlockLocations()}}.
> The lease recovery will be retried in about an hour by the namenode. If the nodes are
faulty (usually when there is only one new target), they may not block report until this point.
If this happens, lease recovery throws an {{AlreadyBeingCreatedException}}, which causes LeaseManager
to simply remove the lease without  finalizing the inode.  
> This results in an inconsistent lease state. The inode stays under-construction, but
no more lease recovery is attempted. A manual lease recovery is also not allowed. 

This message was sent by Atlassian JIRA

To unsubscribe, e-mail: hdfs-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: hdfs-issues-help@hadoop.apache.org

View raw message