Re: Pause streaming replication

On Wed, Nov 10, 2021 at 08:36:45PM -0500, Rita wrote:
> Yes, I have read the manual and seen this. It pauses the replication
> (select pg_is_wal_replay_paused()). But on the primary, when I look at
> pg_stat_replication, it still says 'streaming' in the state column. My
> question was how do I get it from 'streaming' to anything else? (
> https://www.postgresql.org/docs/11/monitoring-stats.html#PG-STAT-REPLICATION-VIEW)
> ?

pg_is_wal_replay_paused() pauses WAL *replay* at recovery, but it does
not stop the stream of WAL from the primary to its standbys.

> I want to trigger an alert when 'streaming' isn't there. Or is there a
> better way to do it?

If you want to have some automated test to check a given state of the
replication, you could use a combination of a SIGSTOP on the WAL
receiver of the standby and/or the WAL sender of the primary, with
some pg_terminate_backend() calls, just to throw one idea in the
bucket.
--
Michael