You can use split. For restoring, cat the parts together and pipe the output into a dd command. Without an "if=" argument, standard input is used. You could also have gzip or bzip2 in a pipe to reduce the size of each slice. This will work better if the unused space is zeroed. You can do this by using something like "dd if=/dev/zero of=zerofile bs=512 count=$(($FREEBLOCKS-1))"
I did this to back up my boot partition. It compressed to 1/10 the size of the partition.
Another solution is to create an ext3 partition on the external drive.
Last edited by jschiwal; 02-21-2008 at 08:27 AM.