Re: Multiple postgresql clusters with same version and separate binaries

Thanks for your comments Stéphane!

As a matter of fact, I'm just reading about the pglogical, and that might
be a likely solution :-)
We also use ansible for automated failover, it works nicely.

Thanks,
Erika

On Tue, 8 Jan 2019 at 09:50, Stéphane KANSCHINE <stephane(at)hexack(dot)fr> wrote:

> Le mar. 8 janv., vers 08:13, Erika Knihti-Van Driessche exprimait :
>
> > Hi,
>
> Hey !
>
> > I'm sure I'd regret creationg all the extra work for myself, but.. the
> > customer insists that not all (at least production) applications may go
> > down at the same time.
>
> That's precisely the purpose of services or init script if you prefer.
>
> For a customer, i manage 10 clusters x 5 environments, entirely with 1
> service per cluster and 1 binary per environment. I also use ansible
> to deploy and maintain streaming replication, logical migration,
> monitoring, all based on services. It's easy with Debian packages,
> because service creation is included.
>
> > I have streaming replication in place also, and I think for minor upgrade
> > it won't be a problem to first upgrade standby, resync replication, then
> > failover primary to newer minor version standby (altho I did read that
> this
> > is not supported but will likely work..).
>
> It'll work.
>
> > For major upgrade this isn't an option though, or I would have to
> > implement Slony (I think)..
>
> Why don't you use logical replication ? I recently migrate the 10x5
> clusters from 9.6 to 10 with pglogical in 2 days of work. It was also
> from Red Hat to Debian and i automate cluster per cluster with
> services. Next step is to migrate from 10 to 11, also with logical
> migration, by hand this time, because pglogical don't do so much and
> due to the lack of documentation, i already wrote the missing parts.
>
> > So, just creating separate services isn't really an option, because
> > it won't help me with the upgrades.
>
> It does as the major version is in the service name (i.e.
> postgresql@<version>-<clustername>), you won't have to update it once
> it's written.
>
> Regards,
> --
> Stéphane KANSCHINE - https://www.hexack.fr./ - https://www.nuajik.io./
> ＠ stephane(at)hexack(dot)fr
>  +33 6 64 31 72 52
>