From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Victor Sudakov <vas@sibptus.ru>
To: pgsql-admin@lists.postgresql.org
Subject: Re: A streaming replica catching up
Date: Thu, 22 Apr 2021 09:20:43 +0200
Message-ID: <8ec1143e5f1e45714b415076b3ad7533346e2734.camel@cybertec.at> (raw)
In-Reply-To: <YIDqmtsUEpTK8Krp@admin.sibptus.ru>
References: <YIDqmtsUEpTK8Krp@admin.sibptus.ru>
On Thu, 2021-04-22 at 10:16 +0700, Victor Sudakov wrote:
> After a streaming standby has been down for a time, I know of two
> options for it to catch up with the master:
>
> 1. The replica can fetch all the necessary WAL records via the
> replication protocol from the master (unless max_slot_wal_keep_size is
> not the default -1, all the required WAL archives should be available from
> the master).
>
> 2. The replica can be provided with a restore_command and will fetch
> all WAL files from the WAL archive before starting streaming WAL from
> the master.
>
> Which is the preferred way?
>
> Of course if max_slot_wal_keep_size is limited, the second options seems
> the only safe one.
>
> OTOH, if the master does not write to a WAL archive, only the first
> option is left to us.
Both methods are equally feasible. Which one you choose depends on
your situation, just as you describe in the last two sentences.
Yours,
Laurenz Albe
--
Cybertec | https://www.cybertec-postgresql.com
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: laurenz.albe@cybertec.at, vas@sibptus.ru, pgsql-admin@lists.postgresql.org
Subject: Re: A streaming replica catching up
In-Reply-To: <8ec1143e5f1e45714b415076b3ad7533346e2734.camel@cybertec.at>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox