Re: Database backup mechanism

Doug Knight wrote:
> I would also be interested in any "creative" ways to reduce the size and
> time to backup databases/clusters. We were just having a conversation
> about this yesterday. We were mulling over things like using rsync to
> only backup files in the database directory tree that actually changed.
> Or maybe doing a selective backup of files based on modified times, etc,
> but were unsure if this would be a safe, reliable way to backup a
> reduced set of data.

Most of your virtual-layer filesystems should offer a snapshot facility 
that lets the database think its writing to the files while you see a 
static version. You could rsync that against an older file-level copy as 
the base copy in a PITR backup.

Note - even with a snapshot facility you need to use PITR or stop the 
database to get a guaranteed working copy.

--   Richard Huxton  Archonet Ltd