On Tue, 1 Dec 2015 11:18:07 +0100 Jehan-Guillaume de Rorthais <[email protected]> wrote:
> On Mon, 30 Nov 2015 15:04:37 -0600 > Ken Gaillot <[email protected]> wrote: > > > On 11/25/2015 06:52 PM, Jehan-Guillaume de Rorthais wrote: > > > Hi guys, > > > > > > While working on our pgsqlms agent[1], we are now studying how to control > > > all the steps of a switchover process from the resource agent. > > > > > > The tricky part here is the 2nd step of a successful swithover with > > > PostgreSQL (9.3+): > > > (1) shutdown the master first > > > (2) make sure the designated slave received **everything** from the old > > > master (3) promote the designated slave as master > > > (4) start the old master as slave > > > > > > As far as we understand Pacemaker, migrate-to and migrate-from > > > capabilities allows to distinguish if we are moving a resource because of > > > a failure or for a controlled switchover situation. Unfortunately, these > > > capabilities are ignored for cloned and multi-state resources... > > > > > > Because of this restriction, we currently don't know from the resource > > > agent code if we should check the designated slave received everything > > > from the old master (controlled switchover) or not (we lost the master). > > > In case of controlled switchover, if the designated slave did not > > > received everything from the master, we must abort the switchover. ... > > It would be nice to support migration for globally unique clones, and > > the master role of stateful clones. Feel free to submit a feature > > request with what you think the interface should look like. > > Thanks, I will. done: http://bugs.clusterlabs.org/show_bug.cgi?id=5259 Let me know if I can do anything. With enough direction (I don't have lot of R&D time), I might be able to help forging a patch. Regards, _______________________________________________ Developers mailing list [email protected] http://clusterlabs.org/mailman/listinfo/developers
