Um if we are redesigning backup stuff, I have a question.

Should backups be tape-focused, or considered a form of
remote long-term stable storage?

Personally, the reasons I've used backups are, in order of frequency:

	-- accidentally nuking a file that was important
	-- needing back an old version of a file that has been unlinked
           in the past
	-- moving files off a disk, repartitioning, and moving them back on
	-- replacing a dying disk that tended to crash and corrupt files
	   with all the fun of figuring out which files were corrupted

finding older versions of files fast is nice.   A colleague and I
have been spoiled by IBM's ADSM for a while, and so mostly are
looking at ways to make backups to a large RAID array, which then
would put long-term erased/overwritten versions of things onto
long-term stable media in something like LRU fahsion.

The fun is in figuring out how to support the (ick) multiple OS platforms...

The plan9 mindset (http://plan9.bell-labs.com/plan9/doc/README.html, look
for "Backup and Recovery") is sorta neat, too, for that matter.

	Sean.