dumping to TK-70

[Alan's Home for Wayward Notes File.]

In article <517 at mesrx.UUCP>, bbraden at mesrx.UUCP (Bill Braden) writes:
> Making the jump from VMS system managment to ULTRIX system managment
> sure is fun.  Here is a little problem that some of you expirenced
> super users might be able to help with.
> 
> I am doing a level 0 dump of my file systems to TK-70.  The file system
> in question is under 200mb.  A TK-70 is supposed to hold 295mb.  Why 
> does dump require 3 tapes?
> 
> [ Example dump deleted. ]

	What version of ULTRIX are you running?  Before V4.0 dump(8)
	calculated how much tape a particular backup based on the
	length of tape, density, inter-record gap, phase of moon,
	etc.  For nice normal 9 track tape drives this always worked
	well.  For nearly anything else the algorithm breaks and you
	sometimes have to hand dump(8) slightly bogus numbers to get
	it estimate correctly.  Previously these estimates were used
	to decide when to go to the next tape of a volume.  I think
	in V4.0 it just keeps dumping until it hits EOT, then goes to 
	the next tape.
> 
> Have I got something setup strange, does the system think its a TK-50?
> Should I be using B,d or s options?  Is dump just a tape hog? Or should
> I just stick to VMS?

	I think more recent versions of dump(8) will say what kind
	of tape they think they are talking to.  I didn't look closely
	enough at your listing to see.  If you're running V4.0 then
	there shouldn't be a problem.  Otherwise check the release
	notes to see if says what the incantation is for a TK70 on 
	your particular version.
> 
> --Bill Braden  (Measurex Inc.)
> 
> 					Onward Through the Fog!


-- 
Alan Rollow				alan at nabeth.enet.dec.com