On Mon, Aug 26, 2019 at 5:21 PM Mai Peng <maily.peng@xxxxxxxxxxxxxxxxx> wrote: > > Hello, > > I’ve got several times this error : "requested WAL segment 000000020000A01A0000004F has already been remove". I think it’s due 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
