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From Harsh J <ha...@cloudera.com>
Subject Re: cdh4 HA fencing fails when the other node is down
Date Thu, 24 Jan 2013 04:15:52 GMT
Hi Sagar,

Moving the discussion to cdh-user@cloudera.org as you're asking a CDH
specific question here. List can be subscribed at

Please take a look at the discussion at
and Todd's specific reply there on why a simple fencer won't work for
all scenarios. Using QJM only complements use of ZKFC for Automatic
Failover, does not replace it. QJM is a storage method, while ZKFC
continues to be used for the actual failover-control.

On Thu, Jan 24, 2013 at 7:05 AM, S Naik <snaik@attributor.com> wrote:
> Hi,
> I am trying to setup HA Namenode using cdh4, zkfc.
> It works great when I kill -9 the active namenode.
> But if I reboot/shutdown the host with active namenode. Failover fails.
> The ZKFC complains fencing not succesful.
> It has no route to host exception.
> Is this expected ?
> I looked into mailing list.
> It seems that the fix is to move away from zkfc and use quorum based
> auto failover.
> But, this should be a pretty common requirement and I would think
> there will be a solution for this scenario (With zkfc).
> Please guide me/point me to solution.
> -Sagar

Harsh J

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