Message-ID: <82666d95c1c837ce600bc2a3f212f8ebbc1f5b22.camel@cybertec.at>
Subject: Re: struggling with logical replication and WAL segments removed
 even with max_slot_wal_keep_size = -1
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Sbob <sbob@quadratum-braccas.com>, pgsql-admin@lists.postgresql.org
Date: Sun, 04 Jan 2026 17:29:14 +0100
In-Reply-To: <e0c88962-07a4-400b-84d6-b7d142a36ac1@quadratum-braccas.com>
References: <e0c88962-07a4-400b-84d6-b7d142a36ac1@quadratum-braccas.com>
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On Sat, 2026-01-03 at 11:28 -0700, Sbob wrote:
> we have been fighting logical replication for some timetgres v14,=C2=A0=
=20
> max_slot_wal_keep_size =3D -1 but I still get this kind of error on the=
=20
> publisher every few days:
>=20
> ERROR:=C2=A0 requested WAL segment 00000002000009D6000000AB has already b=
een removed

What is the "wal_status" of the replication slot in "pg_replication_slots"?

Unless you are hitting a bug (what is you minor version?), I'd say that som=
e
rogue software is removing files from "pg_wal".

Compare the "restart_lsn" from "pg_replication_slots" with the available
WAL segments on the primary.

Yours,
Laurenz Albe