how to identify how much data is on tape (or can fit on tape)?

[Sergey Akifiev_1]

hi
the question is in subject. :-)
i've been trying to put exports of an oracle database on LTO1 tape.
that is said, that LTO1 can hold up to 200GB of data (compressed). but oracle exports known to compress even better, then 2:1.
what if i waste half of tape, when choosing VOLSIZE of 200GB in exp utility?
Thanks in advance and sorry for my english :-)

[Peter Godron]

Sergey,
volsize=0 indicates variable length.
Also see:
http://www.lazydba.com/oracle/0__68994.html

Depending on how you back up, you would get indicators how much data was backed up (with dd for example the number of blocks written etc.)

[Peter Godron]

Sergey,
sorry to see that " 1-3: The answer didn't really help answer my question, but thanks for your assistance! "

It may be useful, if you could expand on the solution you are looking for. The volsize will not "waste" any tape, it only indicates how much oracle should expect to write to the tape , before it asks for a new one.

Example:
your export would result in 100Gb to tape
1. with volsize=0 everything fits on one tape
2. with volsize=50M the export will write 50M of data, then requests a new tape.

[Sergey Akifiev_1]

and how much of the tape that 100GB will use?