Back Up Multiple Computers on One External Drive
ArloG asked the Storage forum if one can backup more than one PC onto a single external hard drive.
Probably. It depends on what backup software you're using. The vast majority of backup programs allow you to identify the target (where the backups are placed) as a folder. There's no problem putting multiple backup folders onto the same drive.
There are exceptions. Rebit, a wonderfully simple backup program that's pretty much just plug-and-play, requires a drive all to itself. But off-hand, that's the only one I can think of.
Read the original forum discussion.