Re: Index corruption issue after migration from RHEL 7 to RHEL 9 (PostgreSQL 11 streaming replication)

On Thu, 23 Oct 2025 at 17:21, Greg Sabino Mullane <htamfids(at)gmail(dot)com> wrote

pg_dump is the most reliable, and the slowest. Keep in mind that only the
> actual data needs to move over (not the indexes, which get rebuilt after
> the data is loaded). You could also mix-n-match pg_logical and pg_dump if
> you have a few tables that are super large. Whether either approach fits in
> your 24 hour window is hard to say without you running some tests.
>

Long time ago I had a similar problem and did a "running with scissors"
restore. This means:

1.- Prepare normal configuration, test, etc for the new version.
2.- Prepare a restore configuration, with fsync=off, wallevel=minimal,
whatever option gives you any speed advantage.

As the target was empty, if restore failed we could just clean and restart.

3.- Dump, boot with the restore configuration, restore, clean shutdown,
switch to production configuration, boot again and follow on.

Time has passed and I lost my notes, but I remember the restore was much
faster than doing it with the normal production configuration. Given
current machine speeds, it maybe doable.

Francisco Olarte.