On Tue, 5 Apr 1994 14:42:43 PDT Joseph A. Faracchio said:
>    1) I need duplication of tapes for operational mistakes:
>       lost (misplaced) tape, dropped tape, overwritten tape, etc.
>       These twins will be stored near each other and be kept identical
>       by simultaneous writing on an as needed realtime basis.
>       Mounted at the same time there is no chance for mixing them up.
>       *The image of this scenario makes me lose sleep*

I agree with what Joe said, above, with some slight alterations:

a) Tape twins would be fine, but what I really want is two copies of the
   data, each copy on a different tape.  I don't really care if each tape
   has an exact twin.

b) We are expecting to use 8mm tapes, and I am concerned about tape wearout
   moreso than I am about operational mistakes (all of our tapes will be
   under robotic control).  We will probably take pre-emptive steps to
   replace 8mm tapes before they go bad (hopefully), but we'd really like
   to see 2 copies of the data, especially for archived files.

>    2) I need offsite snapshots for 'real' disaster recovery ...
>       that is easier and faster than Export.

At our site, the backup server will itself be off-site, relative to the
workstations which it is backing up.  However, we do have some workstations
that are in the same location as the ADSM server, so we might use a second
copy for offsite copies in a limited way, if it were available.

..Paul