Re: Linux in-place upgrade

On Mon, Jun 26, 2023 at 1:36 PM Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at>
wrote:

> On Mon, 2023-06-26 at 17:13 +0000, Murthy Nunna wrote:
> > We are planning an in-place upgrade of Linux level from RHEL 7 to RHEL 8
> or RHEL 9.
> > We have several PG clusters running on this server using different
> versions of postgres (pg12, pg13 and pg14).
> >
> > We have couple of plans:
> >
> > 1. Shutdown clusters, unmount disks that contain postgres data and
> wals, upgrade Linux,
> > remount postgres disks and restart postgres clusters
> > 2. Same as above but reinstall postgres (pg12, pg13 and pg14) before
> restarting postgres clusters
> >
> > Questions:
> > 1. Will 1 or 2 or both above work?
> > 2. Is there any official documentation above OS upgrades?
>
> The documentation is here:
> https://www.postgresql.org/docs/current/upgrading.html
>
> It depends on how you installed PostgreSQL. If you used binary packages,
> Option 1 should work fine.
>
> Don't forget to reindex all indexes on strings!
>
> It could be more than just indexes. If there are any partitioned tables
with a partition key of a string, it
could be impacted too. There is a video from the recent PGCon about the
collation changes that
happen going from RHEL7 to RHEL9.
https://www.pgcon.org/events/pgcon_2023/schedule/session/345-sorting-out-glibc-collation-challenges/