HP Tape Library Interface Manager Software - Manual (Page 28)

28 Choosing the Right Configuration Chapter 2
A standard configuration may involve several Fibre Channel (FC) hosts
connected to multiple FC cards. These FC host systems may be connected to
the cards either in a point-to-point (PPP) fashion or through a FC switch. Each
card is then connected to two SCSI tape drives.
The library’s robotics controller may be daisy-chained with one of the SCSI
tape drives or connected directly to an available FC interface card SCSI port,
or direct connect SCSI to host.
Note When daisy-chaining the library’s robotics controller to any LVD
tape drive, the library must have the LVD to HVD converter
(A6324A) installed.
Fibre Channel Port Mode
The IM’s Fibre Channel ports can operate in either NL_Port or N_Port mode.
The IM has the ability to autosense and choose between these modes of
operation.
■ NL_Port - The IM can share a FC Arbitrated Loop with other NL_Port
devices (or HBAs). A single FC switch port acting in FL_Port mode can
also be connected to the loop.
■ N_Port - The IM does not employ the arbitrated loop protocol. This allows
for a more efficient connection to a single FC switch port acting in F_Port
mode.
Some FC switches (such as the HP/Brocade SilkWorm) support either FL_Port
and F_Port modes with autosensing capabilities. Other switches (such as the
HP Surestore Director) only support the F_Port mode. When connecting directly
to a FC switch port, configure the IM in N_Port mode for a more stable and
efficient connection.
Port mode can only be set in the FC Configuration menu via the Telnet
interface. See Configuration Using the Telnet Interface on page 38.