> I was just wondering if there was something which said although certain
> amount of the tape is used as its a DLT  35/70 it has X kb left.

For a particular drive/volume, the manufacturer might have a utility
that can display the exact amount of tape remaining (but due to
compression and error recovery, that amount will a length, not a data
size).  Given particular data, you might be able to come up with a
stronger estimate for how much will fit.

Such utilities would be vendor specific and not supported by Netbackup
or any other backup software I'm aware of.

-- 
Darren Dunham                                           ddunham at taos.com
Senior Technical Consultant         TAOS            http://www.taos.com/
Got some Dr Pepper?                           San Francisco, CA bay area
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