Re: How to start slave after pg_basebackup. Why min_wal_size and wal_keep_segments are duplicated

From: "Andrus" <kobruleht2(at)hot(dot)ee>
To: Paul Förster <paul(dot)foerster(at)gmail(dot)com>
Cc: "pgsql-general" <pgsql-general(at)postgresql(dot)org>
Subject: Re: How to start slave after pg_basebackup. Why min_wal_size and wal_keep_segments are duplicated
Date: 2020-05-31 20:56:05
Message-ID: 69FF4F48E6FE4A63A2EBD820C5B2B3A3@dell2
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-general

Hi!

> On 31. May, 2020, at 21:47, Andrus <kobruleht2(at)hot(dot)ee> wrote:
> replikaator(at)[unknown] ERROR: requested WAL segment 00000001000002CF000000E9 has already been removed
>the message says it all. You need to copy the WAL file 00000001000002CF000000E9 and newer to the replica's pg_wal directory because
>it has been removed >already on the master site.
>Obviously, you can only do that if the files have been archived.

wal files are not archieved.

>Otherwise, you'd have to fully reinitiate the replica.

I have tried to re-initiate replica serveral times in low-use time but this error occurs again.

>Replication will start again as soon as the requested WALs are copied over to the replica.
>Use a replication slot to avoid this situation. If you use a replication slot, the master will only remove WAL files which are not
>needed by any one replica.

If named replication slot is used commands like

vacuumdb --all --full

will cause main server crash due to disk space limit. pg_wal directory will occupy free disk space. After that main server stops.

I tried using wal_keep_segments =180
Will setting wal_keep_segments to higher value allw replication start after pg_basebackup ?

Andrus.

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Adrian Klaver 2020-05-31 21:02:08 Re: pg_dump of database with numerous objects
Previous Message Christophe Pettus 2020-05-31 20:38:11 Re: pg_dump of database with numerous objects