Re: Backup - filesystem snapshots

Chris,

I am having the same problem here and I am considering using SVN for DB
backup, i.e. every snapshot (whichever way you do it, pg_dump seems OK)
gets checked in on a regular basis, then if a table is accidentally
deleted, it can still be checked out and restored. In case you do not
know,
SVN (Subversion, http://subversion.tigris.org) is like CVS (Concurrent
version system).
Of course the SVN repository itself needs to be backed up somewhere.

Best regards,
Dmitri

On Wed, 2006-01-18 at 20:11 +0000, Chris Jewell wrote:

> Hi,
>
> I'm trying to implement a backup strategy for a research database in
> order to prevent again users accidentally dropping their data.
>
> My preferred method would be to create regular snapshots of the data
> directory, and then send this to the backup server using rsync, with
> hard-linking backup rotation. The backup data directories could then be
> examined using a postmaster running on the backup server to extract any
> accidentally deleted tables.
>
> My problem is how to do these snapshots: is it enough to create a hard
> link to the directory, or is there still a risk that a currently running
> transaction might introduce inconsistencies? I guess I could use the
> pg_ctl -m 'Smart' command to stop the database after all clients have
> disconnected, but I sometimes have users leaving their clients connected
> all night. Is there any other way to suspend the postmaster such that
> it finishes its current transaction and queues any other transactions
> while the snapshot is taking place? Any other ideas of how I can create
> such snapshots?
>
> Thanks,
>
> Chris