On Mon, Aug 26, 2019 at 5:21 PM Mai Peng <maily.peng@webedia-group.com> wrote:
>
> Hello,
>
> I’ve got several times this error : "requested WAL segment 000000020000A01A0000004F has already been remove". I think
it’sdue to the lag between our master in EU zone and our standby in US zone.
> How could we configure Postgres to handle this issue?
As others already stated, you can use either wal_keep_segments or
replication_slots with advantages and drawbacks on both sides. One
thing to point out, also, since you did not provide a lot of
information, is that if you have another slave consuming wals, it
could remove (archive_cleanup) segments ignoring other slaves.
Personally, I would go for a replication slot and see if the lag can
be kept under control (i.e., the pg_wal directory does not grow too
much).
Luca