Message-ID: <d84d9729b07ae61edc66ee58c2c413f0b8ecc37b.camel@cybertec.at>
Subject: Re: logical replication, with a replication slot but still getting
 "requested WAL segment has already been removed"
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Sbob <sbob@quadratum-braccas.com>, pgsql-admin@lists.postgresql.org
Date: Tue, 23 Dec 2025 11:17:15 +0100
In-Reply-To: <47840565-33e4-4294-aee3-5fda21bd27e6@quadratum-braccas.com>
References: <47840565-33e4-4294-aee3-5fda21bd27e6@quadratum-braccas.com>
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On Mon, 2025-12-22 at 14:14 -0700, Sbob wrote:
> We have setup logical replication for some very large tables, both publis=
her and subscriber
> are running postgresql v14, however even though the locical replication i=
s using a replication
> slot we keep getting this error:
>=20
> =C2=A02025-12-21 23:25:50.452 UTC [2131314] LOG: =C2=A0logical replicatio=
n apply worker for subscription "bigtables_sub" has started
> =C2=A02025-12-21 23:25:50.987 UTC [2131314] ERROR: =C2=A0could not receiv=
e data from WAL stream: ERROR: =C2=A0requested WAL segment 000000020000089F=
00000098 has already been removed

Look into "pg_replication_slots" on the publisher, perhaps the "wal_status"=
 has changed
to "unreserved" or "lost".  One possible cause for that could be the settin=
g of
"max_slot_wal_keep_size" on the publisher.

Yours,
Laurenz Albe