A Fibre Channel node and port must have a globally unique World Wide Number (WWN). In Cisco UCS WWNs are created as identity pools. A Fibre Channel node (a whole server, storage array) must have a World Wide Node Name (WWNN) and a Fibre Channel port must have a World Wide Port Name (WWPN). Both WWNNs and WWPNs are physical entities; hence, they have a 64-bit address.

The WWNN pool is created as one large pool for the Cisco UCS domain. You can use the default pool in the Cisco UCS Manager SAN tab. However, it is recommended to create a custom WWNN pool for that UCS domain.

A communicating device is a node. A host bus adapter in a server constitutes a Fibre Channel node. For servers and hosts, WWNN is unique foe each host bus adapter (HBA). For a SAN switch, the WWNN is common for the chassis. For midrange storage, the WWNN is common for each controller unit. For enterprise storage, the WWNN is unique for the entire array.

Each server has a unique WWPN for each port of the HBA. For a SAN switch, the WWPN is available for each port in the chassis. For storage, each port has an individual.

The FC Identity Tab in Cisco UCS Manager displays the FC Identity of the devices in the Cisco UCS domain SAN cloud, including the:

• Selected device WWNN or WWPN identifier.

• Whether the identifier is assigned ti a vHBA.

• vHBA to which the identifier is assigned.