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https://issues.apache.org/jira/browse/MAPREDUCE-178?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Amar Kamat resolved MAPREDUCE-178.
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Resolution: Invalid
MAPREDUCE-873 invalidates this.
> Inconsistency in handling lost trackers upon jobtracker restart
> ---------------------------------------------------------------
>
> Key: MAPREDUCE-178
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-178
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Reporter: Amar Kamat
>
> If a tasktracker is lost, the jobtracker kills all the tasks that were
> successful on that tracker and re-executes it somewhere else. In-memory
> datastructures are all cleared up for the lost tracker. Now if the jobtracker
> restarts, the new jobtracker has no clue about the trackers that were lost
> and hence if the lost tracker join back, they will be accepted and all the
> tasks on those tracker will join back. Following are the issues
> - If the running task on the lost tracker is killed, its cleanup attempt will
> be launched. Now the new jobtracker has no idea about this attempt. Also the
> lost tracker can join back and hence there are 2 attempts that are running
> with the same id, one which can move the tip to success and other which moves
> the tip to killed state.
> - Ideally, the lost tracker should be asked to re-init which wont happen now.
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