Quantum Scalar i6000, User Manual

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Chapter 3: Configuring Your Library
Configuring Fibre Channel I/O Blades
204 Quantum Scalar i6000 User’s Guide
Loop ID
You can only set Loop ID when the Topology is set to Loop. You cannot
set the Loop ID if the Topology is set to Point to Point or Loop Preferred.
The loop ID can be set to Soft (default) or to a value from 0 to 125.
When set to Soft, a unique loop ID is selected for the drive. If you
change the Loop ID to a specific value, make sure that each FC tape
drive has a unique loop ID.
Configuring Fibre Channel I/O Blades
FC Host
The
FC Host
command enables you to manually modify host
information and set LUN mappings.
During device discovery, a particular partition or drive could map to a
higher LUN space than is optimal for a particular application. The
FC
Host
command enables you to create a virtual private remapping of
available LUNs for a specific Fibre Channel-attached host. LUN mapping
is required to give hosts access to partitions and devices. You also can
make devices appear to the host as if they were at lower LUNs in order
to optimize system performance.
Note: Use the FC Host command to map partitions when a Fibre
Channel host is connected either to the MCB or to an I/O blade.
Depending on host operating system constraints, it might be necessary
to reboot or reconfigure the host because of device map changes that
result from using the FC Host command.
Caution: If you change LUN mapping after host computers or
applications have already discovered devices, you must
make sure that device discovery occurs again. Device
discovery occurs automatically when you reboot the library.
Some host computers have plug and play capability, which
discovers devices automatically. In general, host
applications do not discover devices automatically.