> On Nov. 20, 2013, 4:16 p.m., kturner wrote:
> > test/system/continuous/hdfs-agitator.pl, line 104
> > <https://reviews.apache.org/r/15650/diff/1/?file=388001#file388001line104>
> >
> >     What are the pros and cons of using this haadmin command vs killing 
> > namenode processes?

Pro haadmin:

* The underlying HDFS instance may not be configured for automatic failover.
* The haadmin command doesn't require knowing where the NameNode processes are 
running within the cluster.
* The haadmin tool is a publicly exposed way of saying "do a failover", whereas 
finding the NameNode to kill will be a heuristic.

Pro killing namenode:

* If you specifically need to test what happens when it's the automatic 
failover process kicking in

Note that I don't think the pro-killing pro is that strong of a pro. The 
haadmin command still needs to transition the active to standby and then the 
standby to active, so systems above HDFS are going to already encounter e.g. 
gaps in there being an active namenode.


- Sean


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On Nov. 18, 2013, 5:13 p.m., Sean Busbey wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://reviews.apache.org/r/15650/
> -----------------------------------------------------------
> 
> (Updated Nov. 18, 2013, 5:13 p.m.)
> 
> 
> Review request for accumulo and Alex Moundalexis.
> 
> 
> Bugs: ACCUMULO-1794
>     https://issues.apache.org/jira/browse/ACCUMULO-1794
> 
> 
> Repository: accumulo
> 
> 
> Description
> -------
> 
> ACCUMULO-1794 adds hdfs failover to continuous integration test.
> 
> 
> Diffs
> -----
> 
>   test/system/continuous/continuous-env.sh.example 
> 830ae86b5bf2398a840b853423755f6dd65f2dc0 
>   test/system/continuous/hdfs-agitator.pl PRE-CREATION 
>   test/system/continuous/start-agitator.sh 
> 52e5a4e82a4564fa624a71f73ad29fa20ba23246 
>   test/system/continuous/stop-agitator.sh 
> b853a55b12f8402606af52e0748ca50daf95ed7f 
> 
> Diff: https://reviews.apache.org/r/15650/diff/
> 
> 
> Testing
> -------
> 
> Ran the hdfs agitator on a CDH4 cluster configured for HA. it successfully 
> caused the active namenode to failover as it went.
> 
> 
> Thanks,
> 
> Sean Busbey
> 
>

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