>I would like to know how much space on the library I will
>gain by doing that    [reducing retentions]

Ofer - That kind of information is very difficult to obtain...
       The size that you can get from the server Contents table is the Aggregate
size, so you would have to try to mesh that with the Backups table where the
backup date is stored.  From the client side, you have Query Backup to report
file sizes, which you'd have to process by backup date vs. your retention
reduction...  As you can see, this is difficult at best, and yields only
approximate values.

You might try reducing your retention/versions values by 1, then run an Expire
Inventory, and then query occupancy to see how much you gained, and extrapolate
from that.

Don't overlook the Move Media command to externalize tapes to your library.
See the Admin Guide for guidance on its usage (topic "Managing a Full Library").

  Richard Sims, BU