Re: warm standby possible with 8.1?

On Tue, Mar 09, 2010 at 05:48:41PM -0500, Greg Smith wrote:
> zhong ming wu wrote:
> >Is it possible to have a warm standby with 8.1?
>
> No.  You can set that up so that it replays an entire pile of log
> files sitting there when you start the server, which it sounds like
> you haven't managed yet because you're trying to treat it like a
> warm-standby.  But 8.1 isn't capable of applying log files one at a
> time; it applies whatever you've got, and then it's done with
> recovery and transitions to live.  You can't just stop the result
> and then feed it the next file, as you've already discovered through
> experimentation.

Guys, I'm afraid there may be some confusion here.  I've got a warm
standby happily running with simple home-made archive and restore
scripts on a legacy Postgresql installation as old as 8.0.  And yes, I
did failover multiple times (I posted a report or two on that to this
list.)

What Zhong isn't going to get is converting the master node to a warm
standby node as easily as by just stopping it and renaming recovery.done
to recovery.conf.  The way to go here is to take a file-level DB backup
from the master node and bootstrap a new warm standby node from it, then
let it catch up with the master node WAL-wise.

Yar