[ClusterLabs] PostgreSQL Automatic Failover (PAF) v2.2.0

[Valentin Vidic]

On Thu, Oct 05, 2017 at 08:55:59PM +0200, Jehan-Guillaume de Rorthais wrote:
> It doesn't seems impossible, however I'm not sure of the complexity around
> this.
> 
> You would have to either hack PAF and detect failover/migration or create a new
> RA that would always be part of the transition implying your PAF RA to define
> if it is moving elsewhere or not. 
> 
> It feels the complexity is quite high and would require some expert advices
> about Pacemaker internals to avoid wrong or unrelated behaviors or race
> conditions.
> 
> But, before going farther, you need to realize a failover will never be
> transparent. Especially one that would trigger randomly outside of your control.

Yes, I was thinking more about manual failover, for example to upgrade
the postgresql master.  RA for pgbouncer would wait for all active
queries to finish and queue all new queries.  Once there is nothing
running on the master anymore, another slave is activated and pgbouncer
would than resume queries there.

-- 
Valentin