Re: lost replication slots after pg_upgrade

On Tue, Oct 13, 2020 at 11:34:27PM +0200, Peter Eisentraut wrote:
> On 2020-10-13 19:23, Pavel Stehule wrote:
> > no, I just missi note, so after upgrade by pg_upgrade I have to recreate
> > replication slots. Some like
> >
> > after pg_upgrade you should to do:
> >
> > a) run analyze .... (it is a known case)
> > b) recreate replication slots - these slots are not removed in the
> > upgrade process.
>
> An argument could be made that pg_upgrade should copy over logical
> replication slots. The normal scenario would be that you pause your logical
> subscriptions, run pg_upgrade on the publisher, then un-pause the
> subscriptions. The subscribers then ought to be able to reconnect and
> continue consuming logical changes. Since the content of the publisher
> database is logically the same before and after the upgrade, this should
> appear transparent to the subscribers. They'll just see that the publisher
> was offline for a while.

I guess that is possible since pg_upgrade resets the WAL location,
though not the WAL contents.

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Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EnterpriseDB https://enterprisedb.com

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