Connecting a Dell PowerVault TL2000 Tape Drive

I need help on how to connect a Dell PowerVault TL2000 to my virtualized environment. I have a Dell R730 poweredge server connected to a Dell MD3221i storage device. i have also connected to this setup a Dell PowerVault TL2000. So what i have done is i have connected a SAS cable from my Dell R730 to the TL2000. 

I run a XenServer 6.5 virtualized environment backing up virtual machines to Dell storage devices. The Dell TL2000 is located at a DR site where the virtual machines are being replicated using the Unitrends Enterprise backup software. i have attached the TL2000 on this end. The problem i have is that i cannot see the tape drive media from the Unitrends software archive to media option.Even when i scan for media devices.  Does anyone know how i can do this or is there something else i need to install?