tk70 density and length

[Quentin Fennessy]

Reply-to: quentin at umb.umb.edu (Quentin Fennessy)

In article <87714 at felix.UUCP> rusty at hplabs.UUCP writes:
>I suspect this is an old question.  I just brought up 4.3bsd tahoe on
>a VAXstation 3200.  When I use dump, I need to tell it both the
>density and length of the tape.  What are these numbers for the TK70
>in high density mode?

A TK70 is 600 feet long, and runs at 10240 bpi density.
This reminds me of a question I have had for a while-
To actually fit 296 MB on a TK70, I have to lie to dump(8) (Ultrix3.0)
and tell it is 4800 feet long!
So, my command line is something like: dump 0uds 10240 4800 /dev/rra0a

Digital has given me this as an answer. I think it is still a question.
Why do I have to say 4800 feet to use 600 feet?

THanks,
	Quentin Fennessy
	ITP boston, inc
	UMass Boston