Re: [Extern] Re: Is a logical replication crash recovery safe?

Markus,
Yesterday EDB published the (open source) pg_failover_slots extension,
aimed at pushing logical slot information on standbys: without it, that
information is kept on the master only, so you have to rebuild the logical
replication topology on switch/fail-overs.
Obviously, if the promoted server is outdated wrt to the lost master, you
could still have problems with subscriptions, although there some
configuration that tries to address that problem too
(standby_slots_min_confirmed).
For the moment being you can find the documentation at EDB's docs
<https://www.enterprisedb.com/docs/pg_extensions/pg_failover_slots>, and
the sources at github.com/EnterpriseDB/pg_failover_slots. I hope the
extension will make quickly its way to PGDG as prebuilt packages.
Best,
g

On Tue, 24 Jan 2023 at 17:08, Zwettler Markus (OIZ) <
Markus(dot)Zwettler(at)zuerich(dot)ch> wrote:

> > -----Ursprüngliche Nachricht-----
> > Von: Christophe Pettus <xof(at)thebuild(dot)com>
> > Gesendet: Dienstag, 24. Januar 2023 16:48
> > An: Zwettler Markus (OIZ) <Markus(dot)Zwettler(at)zuerich(dot)ch>
> > Cc: pgsql-general(at)lists(dot)postgresql(dot)org
> > Betreff: [Extern] Re: Is a logical replication crash recovery safe?
> >
> >
> >
> > > On Jan 24, 2023, at 07:37, Zwettler Markus (OIZ) <
> Markus(dot)Zwettler(at)zuerich(dot)ch>
> > wrote:
> > >
> > > Is a logical replication crash recovery safe?
> >
> > You might want to give more detail about the scenario you are concerned
> about.
> > Changes that are received by a subscriber as part of logical replication
> are WAL-
> > logged, observe transaction semantics, and will be replayed if the
> subscriber
> > crashes and restarts.
> >
>
>
> Sorry. Let me refine.
>
> If I create a logical replication slot and use the replication slot to
> publish some tables.
>
> Will the information in the replication slot be safe for any subscription
> even if a crash recovery happened on the publisher node?
>
>
>