Backup strategies?

[John C. Noble]

References:



	We have a Vax 11/780, Pyramid 98x, masscomp, several (5 or 6)
Microvaxen, several disk based Suns, a Sun server for 10 or so diskless
workstations, and a partridge in a pear tree, all running some version
of unix.  For some reason, we have a problem performing full and
incremental disk backups for all these systems. :-)
	Since these systems are connected via ethernet, we currently
perform a full dump once per week from the various small systems 
(different systems on different days) to the Pyramid and save these dumps 
on tape each morning.  (The Vax and Pyramid are handled separately, using 
traditional backup procedures.)
	However, this solution is at best a temporary one, since
there is no guarantee the free disk space on the Pyramid will last
forever.  In addition, this does not solve the incremental backup problem
(though, a system similar to the full backup procedure could be
implemented, using even more disk space).  Maybe we could make the
Pyramid a "dump server."
	I'm sure there are many other sites with similar configurations.
How do you handle your backups?  Do you let each machine be responsible
for its own backups?  Obviously, if you have slave labor (i.e, students)
traditional backup problems may be satisfactory, though the tape
storage problem would be considerable.  Has anyone made use of the high 
density optical disk WORM drives?
-- 

				John Noble
				JHU/APL
			...seismo!umcp-cs!aplcen!aplvax!jcn