Re: Clean switchover

On Wed, Jun 12, 2013 at 12:55 PM, Mark Kirkwood
<mark.kirkwood@catalyst.net.nz> wrote:
> On 12/06/13 13:15, Stephen Frost wrote:
>>
>> * Fujii Masao (masao.fujii@gmail.com) wrote:
>>>
>>> The attached patch fixes this problem. It just changes walsender so that
>>> it
>>> waits for all the outstanding WAL records to be replicated to the standby
>>> before closing the replication connection.
>>
>>
>> Seems like a good idea to me..  Rather surprised that we're not doing
>> this already, to be honest.
>>
>
> Yeah +1 from here too. This would make clean switchovers for (typically)
> testing scenarios a lot less complex and resource intensive (rebuilding of
> the old master as a slave when you know it is ok is despairing on a huge
> db).
>
> On the related note (but not actually to do with this patch),
> clarifying/expanding the docs about the various methods for standby
> promotion:
>
> 1/ trigger file creation
> 2/ pg_ctl promote
> 3/ renaming/removing recovery.conf
>
> and the differences between them would be great. For instance I only
> recently realized that method 3) means the promoted standby does not start a
> new timeline (incidentally - could this be an option to pg_ctl promote)
> which is very useful for (again) controlled/clean switchovers.

In 9.3, you no longer need to worry about the increment of timeline
after the promotion because the standby can automatically follow
the timeline switch.

Regards,

-- 
Fujii Masao