backup capacity problem

[dskny]

With DLT 40/80 tapes...the backup completes 58 gigs and then it asks for another tape? If I stick the same tape back in, it says this:

The media provided to continue the backup already contains data from one or more sets created during this operation.
The operation can not be continued

So I put in a new tape and it completes the backup with another 4 gigs.

Why does it not complete the back up one tape when it is supposed to be 80gigs?
thanks

 

[SQLBill]

Did you set Backup Exec to allow compression? Which type of compression are you doing (hardware or software)?

Are you appending or overwriting on the first tape?

-SQLBill

 

[justin2000]

dskny - thats actually pretty good compression you are getting from the tape. The compression you will get, all depends on what you are actually backing up.

Check out this technote from Veritas -

http://seer.support.veritas.com/docs/199542.htm

The error you are getting when you put the first tape back in is normal, as it is protecting the tape from being overwritten by the same backup.