When you install Backup Exec, support for every single-drive virtual tape library is included. The Virtual Tape Library Unlimited Drive Option enables support for all additional drives in each virtual tape library.
You can find a list of compatible devices at the following URL:
http://entsupport.symantec.com/umi/v-269-2
You can find license information for the Virtual Tape Library Unlimited Drive Option at the following URL:
http://entsupport.symantec.com/umi/V-269-21
To install the Virtual Tape Library Unlimited Drive Option, add a license key.