Re: upgrade to repmgr3 - Mailing list pgsql-general

From Martín Marqués
Subject Re: upgrade to repmgr3
Date
Msg-id CAPdiE1zauZjmWp9MU5oZC3AXztSnj+ese9D-YkK5HzBRW5JkeA@mail.gmail.com
Whole thread Raw
In response to Re: upgrade to repmgr3  (Pekka Rinne <tsierkkis@gmail.com>)
List pgsql-general
Hi,

2016-08-11 7:54 GMT-03:00 Pekka Rinne <tsierkkis@gmail.com>:
>>
>> Do you by chance have synchronous replication set? That ps output alone
>> doesn't say much, but being stuck on COMMIT normally points to failure
>> to sync the replication on a standby.
>>
>
> Yeah, I learned that repmgr3 actually writes to DB during promote. Repmgr2
> does not do that. And if the failed master itself is on the synchronized
> replicas list then the promote command hangs in commit as its not possible
> to sync to that failed node. Solution seemed to be to temporarily comment
> out synchronized replicas from postgresql.conf in new master and reload
> configfile. Then the promote command returns in command line.

Solution would be having at least 2 standbys listed in
synchronous_standby_names. With only one node name there, if the
standby goes down, all the transactions that make changes will hang at
commit execution.

Regards,

--
Martín Marqués                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services


pgsql-general by date:

Previous
From: Pekka Rinne
Date:
Subject: Re: upgrade to repmgr3
Next
From: Rakesh Kumar
Date:
Subject: Serializable read and blocking