How to use SSO to share a Robotic tape library

hi again :)

first of all i think BE administration guide is so confusing and incomplete , i cannot find anything about how to use SSO , Physical Server Backup over FC and ....but the forum is great.

i want to share a robotic tape library between 2 BE server (one of them is CAS and other one is Managed BE Server.)

i got ESO license , tape library is on SCL(4 Drives and 48 Media Slots)

Tape device is connected to SAN network and Both BE servers can see it on Storage tab , now how can i share it between two servers? i cannot find anything about SSO in BE, no setting , no wizard nothing. please help me.