BTW, make sure you get the latest microcode on those drives. We just went thru 
a series of catridges becoming unavailable and having to do volume restores and 
losing data in the process.

>>> ilja.coolen AT ABP DOT NL 05/03/01 06:38AM >>>
As far as i know AIX doesn't support automatic failover for tape devices by
default. For this to accomplish you need to build it yourself, or install
third party software.

As an example: we have connected an ESS to our S70 - ADSM Server using 4 FC
adapters. AIX correctly detects each harddisk 4 times. You can check this by
the serialnumber. Using Subsystem Device drivers (used to be Datapath
Optimizer) you can map each unique harddisk per adapter to one virual
device.

See the clipping:

(rs6sv057-root) /home/root> datapath query device 12

DEV#:  12  DEVICE NAME: vpath13  TYPE: 2105F20   SERIAL: 50716694
=================================================================
Path#              Adapter/Hard Disk    State     Mode     Select     Errors
    0                 fscsi0/hdisk15     OPEN   NORMAL    1389355          0
    1                 fscsi2/hdisk31     OPEN   NORMAL    1385889          0
    2                 fscsi3/hdisk62     OPEN   NORMAL    1385217          0
    3                 fscsi4/hdisk47     OPEN   NORMAL    1368531          0

You can see by the serial that all 4 harddisks are identical. The load to
the selected disks will be equally distibuted over al 4 paths. If one to
three paths fail, the remaining paths will continue to work without
disturbance. After reconnecting the failed paths, all load will
automatically be devided over the available paths.

This is what you would need to look for to connect your drives. What does
IBM say?
Good luck.

BTW: I woul'd imagine that your drive itself is most likely to fail, not
your connection. I think the cost will not weigh up against the gain.

Ilja Coolen.