On Tue, 2004-11-23 at 16:36 -0600, Jim Crumley wrote: > On Wed, Nov 24, 2004 at 05:55:15AM -0600, John Reese wrote: > > I too need to back up some pretty hefty systems (~ 8 GB), so not only > > will I need to write to DVD instead of iso9660 (<= 700 MB), but I'll > > also need to span DVDs. I looked up some manuals on dd and mkisofs, and > > it is not clear to me that either of them can do this. Anyone else out > > there encounter this problem? Better yet, has anyone resolved it? > > I don't think that there's a way around this problem directly > with dd, but there's quite a bit of backup software that can deal > with the problem. With dd, can't you just specify bs=BYTES and count=BLOCKS, to copy only as many bytes as will just (but maybe not quite) fill up one DVD, and then run dd the nth time with skip=BLOCKS, specifying the number of blocks you already copied? i.e. DVD 1: dd if=/dev/hdrive of=/dev/dvd-r bs=1K count=4MB DVD 2: dd if=/dev/hdrive of=/dev/dvd-r bs=1K count=4MB skip=4MB DVD n: dd if=/dev/hdrive of=/dev/dvd-r bs=1K count=4MB skip=4(n-1)MB and to restore (use at YOUR own risk!): DVD 1: dd if=/dev/dvd-r of=/dev/hdrive bs=1K count=4MB DVD n: dd if=/dev/hdrive of=/dev/dvd-r bs=1K count=4MB skip=4(n-1)MB Of course, you may get better performance with a different block size, and I'm assuming 4GB disks, and not sure whether you should say 4MB (4,000,000) or 4M (4,194,304) but it certainly seems possible to me that you can use dd. You'd be doing a simple 'image' backup here though, with no simple way to access individual files or directories. Anyone see a reason why this wouldn't work? I'm not sure you can just write to a DVD-R using dd... maybe you need to make an image file first? If it's not clear, I have NOT tested this in any way! I was just reading the dd manpage. I've only used dd to copy floppies and hard drives (to other hard drives). Eric _______________________________________________ TCLUG Mailing List - Minneapolis/St. Paul, Minnesota Help beta test TCLUG's potential new home: http://plone.mn-linux.org Got pictures for TCLUG? Beta test http://plone.mn-linux.org/gallery tclug-list at mn-linux.org https://mailman.real-time.com/mailman/listinfo/tclug-list