Re: pg_rewind in contrib

From: Satoshi Nagayasu <snaga(at)uptime(dot)jp>
To: Heikki Linnakangas <hlinnakangas(at)vmware(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgreSQL(dot)org>
Subject: Re: pg_rewind in contrib
Date: 2014-12-16 09:57:16
Message-ID: 549001FC.4020705@uptime.jp
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 2014/12/16 18:37, Heikki Linnakangas wrote:
> On 12/16/2014 11:23 AM, Satoshi Nagayasu wrote:
>> pg_rewind assumes that the source PostgreSQL has, at least, one
>> checkpoint after getting promoted. I think the target timeline id
>> in the pg_control file to be read is only available after the first
>> checkpoint. Right?
>
> Yes, it does assume that the source server (= old standby, new master)
> has had at least one checkpoint after promotion. It probably should be
> more explicit about it: If there hasn't been a checkpoint, you will
> currently get an error "source and target cluster are both on the same
> timeline", which isn't very informative.

Yes, I got the message, so I could find the checkpoint thing.
It could be more informative, or some hint message could be added.

> I assume that by "target timeline ID" you meant the timeline ID of the
> source server, i.e. the timeline that the target server should be
> rewound to.

Yes.
Target timeline I mean here is the timeline id coming from the promoted
master (== source server == old standby).

I got it. Thanks.

I'm going to look into more details.

Regards,

>
> - Heikki
>

--
NAGAYASU Satoshi <snaga(at)uptime(dot)jp>

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message David Rowley 2014-12-16 10:04:13 Re: Using 128-bit integers for sum, avg and statistics aggregates
Previous Message Mark Cave-Ayland 2014-12-16 09:53:01 Re: Commitfest problems