I'll try to answer your questions but there were a lot! The drives in both 
libraries are IBM LTO4 drives. Both libraries currently have different version 
library code although the faulty library has been upgraded several times to 
different versions as they were available, and the problem still occurred. Both 
libraries are connected to the same TSM server and each is on a different HBA. 
I've tried man different zoning options and they solved nothing. The LTO 4 
drives have also been upgraded to newer firmware levels as they have become 
available., again solving nothing. I've looked in the SAN switch and in TSM and 
see nothing explaining why the robot is going offline. I've sent several logs 
from the robot itself and STK/SUN/ORACLE support says they see no errors except 
that the robot has gone offline. They have said when visiting, that the robot 
seems to vibrate/shimmy sometimes which is why they think it Is going offline. 
They also told me that there was a known issue in previous library firmware 
versions, that if the management Ethernet cable was plugged in, it could cause 
the robot to go offline (something to do with surges from the network switch) 
but this was supposedly fixed in the version we are running. Currently we have 
the Ethernet unplugged (remember data goes across fiber only) to see if this 
solves anything. Unfortunately it may be a month or longer before we even know. 
Absurd! Hopefully that answered some of all of your questions.
Thanks for responding btw.