Message-ID: <d81ec45c68ef8fa4101fc12b4f6d2604cfd34139.camel@cybertec.at>
Subject: Re: Replication failed
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Rambabu V <ram.wissen@gmail.com>
Cc: Sreejith P <sreejith@lifetrenz.com>, pgsql-admin@lists.postgresql.org
Date: Mon, 21 Dec 2020 04:50:02 +0100
In-Reply-To: 
 <CADtiZxo_rQDTMX0iHhFutihjs=Q2UOAcgdGYisfT9B+hQCD6Dg@mail.gmail.com>
References: <E73F4CFB-E322-461E-B1EC-82FAA808FEE6@lifetrenz.com>
	 <9492f3e4fff86b6fcb1d064d680920e8579d9c37.camel@cybertec.at>
	 <CADtiZxo_rQDTMX0iHhFutihjs=Q2UOAcgdGYisfT9B+hQCD6Dg@mail.gmail.com>
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On Mon, 2020-12-21 at 07:46 +0530, Rambabu V wrote:
> On Fri, Dec 18, 2020 at 2:13 PM Laurenz Albe <laurenz.albe@cybertec.at> wrote:
> 
> > On Fri, 2020-12-18 at 00:56 +0530, Sreejith P wrote:
> > > We had 1 M x 4 slave server streaming replication using Postgres 10. Was working successfully for long time.
> > > 
> > > Suddenly all replication servers got failed and getting following message.
> > > 
> > > 2020-12-17 22:24:32 +04 [1587]: [357-1] db=,user=LOG:  invalid contrecord length 2722 at AEA/A1FFF9E0.
> > > 
> > > Requesting help for identifying root cause.
> > 
> > Looks like this problem:
> > https://postgr.es/m/77734732-44A4-4209-8C2F-3AF36C9D4D18%40amazon.com
> > 
> > Was there a crash on the primary sever?
> > 
> > There is a patch under development at this thread:
> > https://postgr.es/m/CBDDFA01-6E40-46BB-9F98-9340F4379505%40amazon.com
> > 
>
> please let us know how to apply the patch, we are able to see below attachments , once downloaded how to apply this patch.
> 
> Attachment	Content-Type	Size
> repro_helper.patch	application/octet-stream	1.3 KB
> ready_file_fix.patch	application/octet-stream

This is still under development, so you should not consider using the patch in
a production system.  The bug is only triggered by a rare coincidence (crash
on while a WAL record is written that spans more than one segment).

But if you want to review the patch
(see https://wiki.postgresql.org/wiki/Reviewing_a_Patch)
to help getting it applied soon, that would be great.

You'd have to read the documentation about building PostgreSQL from source.
The path is applied with the program "patch", typically with

patch -p1 <../ready_file_fix.patch

while you are inside the git repository.

You need some familiarity with building C programs from source.

Yours,
Laurenz Albe
-- 
Cybertec | https://www.cybertec-postgresql.com