On Wed, Nov 16, 2011 at 12:55 PM, Attila Megyeri <amegy...@minerva-soft.com>wrote:
> Hi Florian, > > -----Original Message----- > From: Florian Haas [mailto:flor...@hastexo.com] > Sent: 2011. november 16. 11:49 > To: The Pacemaker cluster resource manager > Subject: Re: [Pacemaker] Postgresql streaming replication failover - RA > needed > > Hi Attila, > > On 2011-11-16 10:27, Attila Megyeri wrote: > > Hi All, > > > > > > > > We have a two-node postgresql 9.1 system configured using streaming > > replicaiton(active/active with a read-only slave). > > > > We want to automate the failover process and I couldn't really find a > > resource agent that could do the job. > > That is correct; the pgsql resource agent (unlike its mysql counterpart) > does not support streaming replication. We've had a contributor submit a > patch at one point, but it was somewhat ill-conceived and thus did not make > it into the upstream repo. The relevant thread is here: > > http://lists.linux-ha.org/pipermail/linux-ha-dev/2011-February/018195.html > > Would you feel comfortable modifying the pgsql resource agent to support > replication? If so, we could revisit this issue and potentially add > streaming replication support to pgsql. > > > Well I'm not sure I would be able to do that change. Failover is > relatively easy to do but I really have no idea how to do the failback part. And that's exactly the reason why I haven't implemented it yet. With the current way how replication is done in PostgreSQL there is no easy way to switch between roles, or at least I don't know about a such way. Implementing just fail-over functionality by creating a trigger file on a slave server in the case of failure on master side doesn't create a full master-slave implementation in my opinion. > I will definitively have to sort this out somehow, I am just unsure > whether I will try to use the repmgr mentioned in the video, or pacemaker > with some level of customization... > > Is the resource agent that you mentioned available somewhere? > > Thanks. > Attila > > > > _______________________________________________ > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: > http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker > -- Serge Dubrouski.
_______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker
