Technical data

selective access in case there are other systems or clusters that are
connected to the same switch as the cluster.
Record the unit name of each partition with the intended use for that
partition (Table 6–4).
____________________ Note _____________________
In a multiple-bus failover, dual-redundant configuration,
you can balance the I/O load by specifying the controller
through which the unit will be accessed. Use the
PREFERRED_PATH switch to the add unit or set unit
ACL commands (PREFERRED_PATH = this_controller
or PREFERRED_PATH = other_controller).
All partitions of a container must be addressed through
the same controller. If you set PREFERRED_PATH for one
partition, all partitions of that container inherit the same
path.
2 Sets an identifier for each storage unit. Use any number between
1 and 9999.
To keep your storage naming as consistent and simple as possible,
consider using the unit number of the unit as its UDID. For instance, if
the unit number is D133, use 133 as the UDID. Note, however, that the
identifier must be unique. If you have multiple RA8000 or ESA12000
storage arrays, a unit number such as D133 might not be unique across
the storage arrays.
The identifier you select shows up as the UDID in the wwidmgr -show
wwid display. The WWID manager uses it when setting the device
unit number and boot_def_dev console environment variable. The
identifier also shows up during the Tru64 UNIX installation to allow
you to select the Tru64 UNIX installation disk.
The identifier is also used with the hardware manager view devices
command (hwmgr -view devices) to locate the /dev/disk/dsk
n
value.
____________________ Note _____________________
We recommend that you set the identifier for all Fibre
Channel storagesets. It provides a sure method of identifying
the storagesets. Make the identifiers unique numbers within
the domain (or within the cluster at a minimum). In other
words, do not use the same identifier on more than one
Using Fibre Channel Storage 6–59