Re: Using rsync for base backups for PITR

["Scott Whitney" <swhitney(at)journyx(dot)com>]

In the same way that you don't have a valid archive while the tar is
running, no? In either case, I have to archive the WAL segments used during
the file system backup, right?

Is rsync a supported method for a warm standby server? Specifically, I'm
thinking about:
http://www.taygeta.com/ha-postgresql.html 

-----Original Message-----
From: Bruce Momjian [mailto:bruce(at)momjian(dot)us] 
Sent: Oct 10, 2007 11:39 AM
To: Scott Whitney
Cc: pgsql-admin(at)postgresql(dot)org
Subject: Re: [ADMIN] Using rsync for base backups for PITR

Scott Whitney wrote:
> I'm reading conflicting information on this. Is this a supported
technique?
> 
> start_backup
> rsync the initial base backup
> stop_backup
> 
> Then, periodically,
> start_backup
> rsync again
> stop_backup
> 
> It's my opinion that this wouuld significantly cut down the 30GB base
backup
> I'll need to take for each PITR.

Uh, well, yes, that will work, but you don't have a valid archive
_while_ the rsync is happening.  I think that would be a problem if
there was a failure during the rsync update.

-- 
  Bruce Momjian  <bruce(at)momjian(dot)us>        http://momjian.us
  EnterpriseDB                             http://postgres.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +