Promotion of standby to master

Started by Andy Chambersalmost 14 years ago2 messagesgeneral
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#1Andy Chambers
achambers@mcna.net

I understand that it's possible to promote a "hot standby" pg server
simply by creating the failover file.  In a scenario where there are
multiple standby servers, is it possible to point the other standby
servers to the new master without creating a new base backup?

When I tried to do this, I ran into the "timeline 2 of the primary
does not match recovery target timeline 1". I'm just trying to figure
out if that's because the procedure I followed to promote the standby
was wrong or because it's just not possible.

Thanks,
Andy

--
Andy Chambers
Software Engineer
(e) achambers@mcna.net
(t) 954-682-0573

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#2Ben
bench@silentmedia.com
In reply to: Andy Chambers (#1)
Re: Promotion of standby to master

On Jun 29, 2012, at 12:16 PM, Andy Chambers wrote:

I understand that it's possible to promote a "hot standby" pg server
simply by creating the failover file. In a scenario where there are
multiple standby servers, is it possible to point the other standby
servers to the new master without creating a new base backup?

When I tried to do this, I ran into the "timeline 2 of the primary
does not match recovery target timeline 1". I'm just trying to figure
out if that's because the procedure I followed to promote the standby
was wrong or because it's just not possible.

On your slaves, you need to have the line:

recovery_target_timeline=latest

This allows the slaves to notice that a new timeline has started and move to it. The one gotcha is that you have to make sure to promote a slave which is most ahead in terms of replication; otherwise, if you promote a slave which is further behind than another slave, and that could cause you grief when the lagging slave tries to replicate from the new master.