TS7700 Tape Attach -- Supported Tape Libraries

The TS3500 Tape Library contains:
Tape drives
The TS7700 tape attach supports a minimum of four and a maximum of 16 tape drives. When connected to a TS3500 Tape Library, 16 tape drives (TS1160, TS1150, TS1140, TS1130, TS1120, or 3592 J1A) can be used, though at least two TS3500 Tape Library frames are required. The TS1150 tape drives can be mixed with one other 3592 tape drive type but the total count cannot exceed 16.
Tape cartridges
The tape cartridges can contain data for multiple virtual volumes and are sometimes referred to as physical stacked volumes.
The TS4500 Tape Library contains:
Tape drives
The TS7700 supports a minimum of four and a maximum of 16 tape drives. When connected to a TS4500 Tape Library, 16 tape drives (TS1160, TS1150, TS1140) can be used, though at least two TS4500 Tape Library frames are required.
Tape cartridges
The tape cartridges can contain data for multiple virtual volumes and are sometimes referred to as physical stacked volumes.
Important:

A TS7700 tape-attach cluster that is attached to a TS3500 or TS4500 Tape Library can be used in a grid configuration. Each TS7700 tape-attach cluster in a grid can be attached to a separate physical library, or the clusters can share the same physical library.

However, sharing a physical library is not recommended and does not conform to best practices. A single library in a grid configuration limits overall performance since systems in the same grid are busy during the same batch windows. Furthermore, mount requests occur during these same peak demand times, limiting performance. A single library in a grid configuration also negates the advantage of independent and redundant subsystems for high availability. The redundancy available on the TS3500 or TS4500 Tape Library (dual accessors, dual grippers, dual power, and the like) can help to mitigate this increased risk, but is still not considered the best practice.