Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual page 531

Configuring Domain Parameters
The 0 (zero) value can be configured only if you use the preferred option.
Note
If you do not configure a domain ID, the local switch sends a random ID in its request. We recommend that
you use static domain IDs.
When a subordinate switch requests a domain, the following process takes place (see the figure below):
• The local switch sends a configured domain ID request to the principal switch.
• The principal switch assigns the requested domain ID if available. Otherwise, it assigns another available
domain ID.
Figure 46: Configuration Process Using the Preferred Option
The operation of a subordinate switch changes based on three factors:
• The allowed domain ID lists.
• The configured domain ID.
• The domain ID that the principal switch has assigned to the requesting switch.
In specific situations, the changes are as follows:
• When the received domain ID is not within the allowed list, the requested domain ID becomes the
runtime domain ID and all interfaces on that VSAN are isolated.
OL-16597-01
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
About Domain IDs
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