Re: PostgreSQL logical replication depends on WAL segments?

On 22/1/19 8:59 μ.μ., Jeremy Finzel wrote:

> On Tue, Jan 22, 2019 at 12:52 PM Andres Freund <andres(at)anarazel(dot)de
> <mailto:andres(at)anarazel(dot)de>> wrote:
>
> Hi,
>
> On 2019-01-22 11:10:27 -0600, Jeremy Finzel wrote:
> > P.S. do heed the advice of the others and get more familiar with
> the docs
> > around WAL archiving.
>
> Logical replication doesn't normally interact with WAL archiving
> in any
> way, so that seems orthogonal.
>
>
> But he is manually removing WAL files via cron which should normally
> be held until the replication slot doesn't need it anymore.  I do
> believe that is why he is getting errors.  The suggestion is to rely
> on Postgres' WAL archiving rather than removing WAL files manually...

wal retention in pg_wal and wal archiving are different things. The OP
got problems cause he deliberately went on to delete files in pg_wal
which means he used the wrong method to address a wrong situation.

However, if the OP has still those WAL files archived he can use them to
bring logical replication back in synch. Don't ask me how I know :
https://www.postgresql.org/message-id/ae8812c3-d138-73b7-537a-a273e15ef6e1%40matrix.gatewaynet.com

>
> Thanks,
> Jeremy