3 – Planning
Multiple Chassis Fabrics
59021-08 B 3-7
D
3.4.2
Domain ID, Principal Priority, and Domain ID Lock
The following switch configuration settings affect multiple chassis fabrics:
Domain ID
Principal priority
Domain ID lock
The domain ID is a unique number from 1–239 that identifies each switch in a
fabric. The principal priority is a number (1–255) that determines the principal
switch which manages domain ID assignments for the fabric. The switch with the
highest principal priority (1 is high, 255 is low) becomes the principal switch. If the
principal priority is the same for all switches in a fabric, the switch with the lowest
WWN becomes the principal switch.
The domain ID lock allows (False) or prevents (True) the reassignment of the
domain ID on that switch. Switches come from the factory with the domain ID set
to 1, the domain ID lock set to False, and the principal priority set to 254. Refer to
the SANbox2-8c/16 Switch Management User’s Guide for information about
changing the domain ID and domain ID lock using SANbox Manager. Refer to the
”Set Config Command” on page B-32 for information about changing the default
domain ID, domain ID lock, and principal priority parameters.
An unresolved domain ID conflict means that the switch with the higher WWN will
isolate as a separate fabric, and the Logged-In LEDs on both switches will flash
green to show the affected ports. If you connect a new switch to an existing fabric
with its domain ID unlocked, and a domain ID conflict occurs, the new switch will
isolate as a separate fabric. However, you can remedy this by resetting the new
switch or taking it offline then back online. The principal switch will reassign the
domain ID and the switch will join the fabric.
Note: Domain ID reassignment is not reflected in zoning that is defined by
domain ID/port number pair or Fibre Channel address. You must
reconfigure zones that are affected by domain ID reassignment. To
prevent zoning definitions from becoming invalid under these
conditions, lock the domain IDs using SANbox Manager or the Set
Config Switch command.