Greetings,
        My habit in regards to zoning FC tape drives has always been to put
one host HBA in a zone with all the tape drives it should see, and to have a
separate zone for each host HBA.  For example, in a situation with 2 host
HBAs and 10 tape drives, I would have two zones, one with one host HBA and 5
tape drives, and the other with the other host HBA and 5 tape drives.
Pretty simple.

        But an IBM consultant working here is telling me that the best
practice is to have a separate zone for each HBA/tape drive pair.  So in my
example above, I would have 20 zones instead of two.   His claim is that an
individual tape drive can hang all the other drives if they are in the same
zone, but not if they are in separate ones.  Has anyone seen this in real
life?

        This becomes important to me because I am about to put in new SAN
switches, and he wants me to follow this recommendation.  I have 2 TSM
servers with 4 HBAs each, 4 NDMP nodes, and 14 tape drives.  Using my
scheme, I would have 12 zones, with his scheme I would have 56 zones.  That
seems like a lot of zones, and unnecessarily cumbersome.

        Is it really necessary to isolate each HBA/Tape drive into a
separate zone?  Do individual tape drives really hang other drives in their
zone?

Best Regards,

John D. Schneider
Sr. System Administrator - Storage
Sisters of Mercy Health System
3637 South Geyer Road
St. Louis, MO.  63127
Email:  schnjd AT stlo.mercy DOT net
Office: 314-364-3150, Cell:  314-486-2359