To: Robert Treat <xzilla@users.sourceforge.net>
cc: pgsql-admin@postgresql.org
Subject: Re: pitr standby on slave with skewed time 
In-reply-to: <200807111119.46117.xzilla@users.sourceforge.net> 
References: <200807111119.46117.xzilla@users.sourceforge.net>
Comments: In-reply-to Robert Treat <xzilla@users.sourceforge.net>
	message dated "Fri, 11 Jul 2008 11:19:45 -0400"
Date: Fri, 11 Jul 2008 12:15:39 -0400
Message-ID: <6522.1215792939@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Robert Treat <xzilla@users.sourceforge.net> writes:
> Was review a clients config/setup and ran across a pitr warm standby scenario
> where the master machine is set to the current time, but the slave's time is 
> currently sitting back in the month of May. Outside of getting ntp setup on 
> the machine, I am wondering if I need to do anything special with the 
> postgresql setup, or if just setting the correct date on the machine is a 
> safe enough operation that nothing else would need to be done (like re-doing 
> the base backup). Any thoughts? 

AFAIR you should be all right ... PITR only looks at WAL indexes, not
file timestamps.

The slave does watch the current time to decide when to do recovery
restartpoints, so if you were setting the clock *back* by a large amount
it might be wise to stop and restart the slave postmaster.  Forward
should be no problem though.

			regards, tom lane