Skip site navigation (1) Skip section navigation (2)

Re: Warm-standby robustness question

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "David F(dot) Skoll" <dfs(at)roaringpenguin(dot)com>
Cc: pgsql-admin(at)postgresql(dot)org
Subject: Re: Warm-standby robustness question
Date: 2007-12-18 18:55:57
Message-ID: 3149.1198004157@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-admin
"David F. Skoll" <dfs(at)roaringpenguin(dot)com> writes:
> My question is this:  If the master database is fairly busy, gets
> VACUUMed once a day, etc. can we expect the warm standby server
> to work correctly after days/weeks/months/years of log shipping,
> or should we periodically take new base backups?

I don't think the time period is at issue.  Log-shipping should keep the
slave a perfect replica of the master (if it doesn't, we have problems
anyway).  The operational question you need to ask yourself is: if
you haven't swapped to the slave lately, how do you know it will work
when you need it to?

The current backup/restore docs suggest as best practice that you
intentionally swap master and slave periodically, ie, fail over
to the slave and then re-initialize the master as a new slave.
This provides a periodic test that your fail-over mechanisms actually
work, and as a bonus gives you a chance for a maintenance window
on the ex-master before it's brought up as new slave.

			regards, tom lane

In response to

Responses

pgsql-admin by date

Next:From: DeronDate: 2007-12-18 20:30:12
Subject: Set maintenance work mem for pg_restore
Previous:From: David F. SkollDate: 2007-12-18 17:49:19
Subject: Warm-standby robustness question

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group