On Tue, Dec 06, 2005 at 12:07:42PM -0600, Les Mikesell enlightened us: > > > Amanda uses dump or tar for the backups and adds one extra block > > > as a header to each backup. You can strip off the header with > > > dd and restore with dump or tar alone. It was a nice system > > > 15 years ago but hasn't had a lot of development since. It > > > has one big flaw in that it can't split a single filesytem > > > backup across more than one tape even though it can do many > > > hosts/filesystems in one run splitting different backups within > > > the run over different tapes. With todays big disks that's probably > > > fatal. > > > > I hardly consider it fatal. I backup 5.5TB of space (4 FSs) to > > an AIT3 changer without a problem. Also, tape spanning is included > > in the 2.5 branch, which is officially in beta now. > > The really brilliant part of amanda is the way it schedules the > mix of full and incremental runs each night to fill a tape of > a given size. This works nicely when you have a large number > of small filesystems (relative to the tape size) but falls down > badly when a single full nearly fills the tape because it will > start streaming some small runs that are finished first, then > the big one won't fit, and even during amflushes it doesn't > know enough to put the big run on the tape first so you end up > with the small ones that can be grouped in a later amflush. The > tape spanning change may help a lot with this. You can also adjust the dumporder parameter to coerce amanda into doing all the biggest dumps first, or the longest dumps to complete, etc. etc. -- Matt Hyclak Department of Mathematics Department of Social Work Ohio University (740) 593-1263