Re: Documentation to upgrade logical replication cluster

On Thu, Jan 4, 2024 at 2:22 PM vignesh C <vignesh21@gmail.com> wrote:
>
> Hi,
>
> We have documentation on how to upgrade "publisher" and "subscriber"
> at [1], but currently we do not have any documentation on how to
> upgrade logical replication clusters.
> Here is a patch to document how to upgrade different logical
> replication clusters: a) Upgrade 2 node logical replication cluster b)
> Upgrade cascaded logical replication cluster c) Upgrade 2 node
> circular logical replication cluster.
> Thoughts?
>
> [1] - https://www.postgresql.org/docs/devel/pgupgrade.html

Thanks for this. It really helps developers a lot. In addition to the
docs, why can't all of these steps be put into a perl/shell script or
a C tool sitting in the src/bin directory?

I prefer a postgres src/bin tool which takes publisher and subscriber
connection strings as the inputs, talks to them and upgrades both
publisher and subscriber. Of course, one can write such a tool outside
of postgres in their own programming language, but the capability to
upgrade postgres servers with logical replication is such an important
task one would often require it. Therefore, an off-the-shelf tool not
only avoids manual efforts but makes it effortless for the users,
after all, if any of the steps isn't performed as stated in the docs
the servers may end up in an inconsistent state.

Thoughts?

--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com