Re: [EXTERNAL] Re: PostgreSQL-12 replication failover, pg_rewindfails

On Tue, 2020-05-12 at 09:40 +0000, Mariya Rampurawala wrote:
> > but if the target cluster ran for a long time after the divergence,
> > the old WAL files might no longer be present. In that case, they can
> > be manually copied from the WAL archive to the pg_wal directory, or
> > fetched on startup by configuring primary_conninfo or restore_command.
> 
> I hit this issue every time I follow the aforementioned steps, manually as well as with scripts.
> How long is "long time after divergence"? Is there a way I can make some
> configuration changes so that I don’t hit this issue?
> Is there anything I must change in my restore command?

What you can do is to use a higher value for "wal_keep_segments".
Then PostgreSQL will keep around that number of old WAL segments,
which increases the chance for "pg_rewind" to succeed.

Yours,
Laurenz Albe
-- 
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