Re: pg_rewind in contrib

> 26 марта 2015 г., в 7:32, Michael Paquier <michael(dot)paquier(at)gmail(dot)com> написал(а):
>
> On Thu, Mar 26, 2015 at 12:23 PM, Venkata Balaji N <nag1010(at)gmail(dot)com> wrote:
>> Test 1 :
>>
>> [...]
>>
>> If the master is crashed or killed abruptly, it may not be possible to do a
>> rewind. Is my understanding correct ?
>
> Yep. This is mentioned in the documentation:
> http://www.postgresql.org/docs/devel/static/app-pgrewind.html
> "The target server must shut down cleanly before running pg_rewind».

You can start old master, wait for crash recovery to complete, stop it cleanly and then use pg_rewind. It works.

>
>> Test 2 :
>>
>> - On a successfully running streaming replication with one master and one
>> slave, i did a clean shutdown of master
>> - promoted slave
>> - performed some operations (data changes) on newly promoted slave and did a
>> clean shutdown
>> - Executed pg_rewind on the old master to sync with the latest changes on
>> new master. I got the below message
>>
>> The servers diverged at WAL position 0/A2000098 on timeline 1.
>> No rewind required.
>>
>> I am not getting this too.
>
> In this case the master WAL visibly did not diverge from the slave WAL
> line. A rewind is done if the master touches new relation pages after
> the standby has been promoted, and before the master is shutdown.
> --
> Michael
>
>
> --
> Sent via pgsql-hackers mailing list (pgsql-hackers(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-hackers

--
Да пребудет с вами сила…
https://simply.name/ru