Many thanks for your reply Simon On Wed, 30 Jun 2004, Simon Riggs wrote: > Date: Wed, 30 Jun 2004 19:29:14 +0100 > From: Simon Riggs <[EMAIL PROTECTED]> > To: [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED] > Subject: Re: [PATCHES] PITR Archive Recovery > > On Wed, 2004-06-30 at 12:27, [EMAIL PROTECTED] wrote: > > Given that log files will be archieved, how can we purge them (ie know for > > sure we won't need them anymore) > > > > Good question - you're right I've not mentioned that. > > The answer is straightforward. Whenever you do a backup, one of the > transaction logs will be the current one. That means any logs before the > earliest one you can see can now be purged from the archive. > > So if you can see: 137,138,139 then that means anything at 136 or before > is able to be discarded. Ok, that's clear... BUT not very easy to put in a backup stagtegy... It may be ok if you user tar or cpio; but surely more complicated if you use backup software like Netvault or Tapeware > > However, I'd recommend keeping more than just one backup, usually 2 or > 3, so the actual purge point is dependant upon your data retention > strategy, possibly linked to tape rotation etc.. > sure > > if I do a backup of the DATA dir, then obviously I won't need the logs > > that were taken before. I can't just delete them all because maybe a few > > will be archived during the backup. > > > I agree > Taking a full physical backup will normally need to exclude the pg_xlog > directory, or at least the current xlog. Since it is being written to > very regularly it is almost impossible to take a clean copy using > standard utilities - though filesystem level utilities work fine. > Would it make sense to have SQL phrases (as I recall from my informix days 10 years ago) like START BACKUP LEVEL 0 where cluster would be archieved on whatever you want, disallowing all writes and SART BACKUP LEVEL 1 where cluster and logs would be archieved letting read/write o databases possible...
> Best regards, Simon Riggs > > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > Best regards -- Olivier PRENANT Tel: +33-5-61-50-97-00 (Work) 6, Chemin d'Harraud Turrou +33-5-61-50-97-01 (Fax) 31190 AUTERIVE +33-6-07-63-80-64 (GSM) FRANCE Email: [EMAIL PROTECTED] ------------------------------------------------------------------------------ Make your life a dream, make your dream a reality. (St Exupery) ---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]