1 HV Installation and Operations Guide

34 Choosing the Right Configuration Chapter 2

A typical configuration may involve several Fibre Channel hosts connected to

multiple FC bridges in a tape library. These Fibre Channel host systems may be

connected to the bridges either in a point-to-point (PPP) fashion or through a

Fibre Channel switch. Each bridge is then connected to multiple SCSI tape

drives plus the SCSI robotics controller via its SCSI buses.

The library’s robotics controller may be daisy chained with one of the SCSI

tape drives or connected directly to an available bridge SCSI port.

Note When daisy-chaining the library’s robotics controller to any LVD

tape drive, the library must have the LVD converter (A6324A)

installed.

Note Magneto-optical jukeboxes are connected to a bridge SCSI port

as a single SCSI connection only. The target devices inside of the

MO jukebox cannot be split among multiple bridge SCSI ports.

The only exception to this is for two-bus MO jukeboxes, which

can divide the internal SCSI targets between two SCSI bus

interfaces.

Fibre Channel Port Mode

The bridge's Fibre Channel port can operate in either NL_Port or N_Port

mode. The bridge has the ability to autosense and choose between these

modes of operation.

■ NL_Port - The bridge can share a Fibre Channel Arbitrated loop with other

NL_Port devices (or HBAs). A single Fibre Channel switch port acting in

FL_Port mode can also be connected to the loop.

■ N_Port - The bridge does not employ the arbitrated loop protocol. This

allows for a more efficient connection to a single Fibre Channel switch port

acting in F_Port mode.

Some Fibre Channel switches (such as the HP/Brocade Silk Worm) 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 a bridge directly to a Fibre Channel switch port, configure the

bridge in N_Port mode for a more stable and efficient connection.