On Wed, Feb 24, 2010 at 10:38:32AM +0100, David Hrbáč wrote: > Dne 24.2.2010 10:00, Agnello George napsal(a): > > We have an issue with one of our clients , they have a mail server with > > the /var/spool/imap partition as 150 GB . They need to take differential > > backup on to /backup partition ( a different HDD of total 250 GB space ) . > > We have tried dar , rsync, rdiff and impasync . But its is not sufficing the > > need as to take a lot of time and consumes a lot of I/O . > > > > Is there any back up solution that you can think of , that can work in this > > situation - open source or proprietary > > Is seems to me, that you are using mbox format. So, differential backup > is hard to achieve. Migrate to maildir, every mail is a file, easy to > backup differentially. rsync and rdiff should handle mbox format okay though. Though I agree Maildir is generally nicer for differential backups. Agnello, how long is "a lot of time"? A backup is always going to have to walk the entire tree and checksum (or at least stat) every file, so there's a minimum cost you're always going to have. How long does a 'find /var/spool/imap -ls' take, for instance? You might want to try brackup (http://code.google.com/p/brackup/). For very large trees of relatively small files it seems to significantly out-perform rsync-based backups. I've got brackup packages in my repository (see http://www.openfusion.net/linux/openfusion_rpm_repository). Cheers, Gavin