A customer has configured a FlexPod solution and is experiencing issues with connectivity from the Cisco Nexus switches to the NetApp AFF…

To troubleshoot Fibre Channel (FC) connectivity between a NetApp controller and a Cisco Nexus switch, an administrator must verify the fabric login (FLOGI) process. The World Wide Port Name (WWPN) is the unique identifier for the specific FC port used for zoning and identification within the fabric. The Fibre Channel ID (FCID) is a 24-bit address assigned by the switch to the port upon a successful FLOGI. Verifying that the controller's WWPN is visible to the switch and has been assigned an FCID confirms that the physical layer is working and the port has successfully joined the fabric, which are critical first steps in troubleshooting.

A. Use the WWNN: The World Wide Node Name (WWNN) identifies the entire device (node), not the specific port used for the connection, making it less precise for port-level troubleshooting.

D. Use Domain ID: The Domain ID identifies a specific switch within the fabric, not the end-point device. It is used for troubleshooting inter-switch links (ISLs), not host-to-storage connectivity.

1. Cisco Nexus 5600 Series NX-OS SAN Switching Configuration Guide, Release 7.x, Chapter: Configuring Fibre Channel Interfaces, Section: Verifying Fibre Channel Connectivity. The documentation explains the use of the show flogi database command, which displays the mapping between the assigned FCID and the device's WWPN, confirming a successful fabric login. This directly establishes both WWPN and FCID as essential elements for verifying connectivity.

2. NetApp TR-4080: FlexPod Datacenter with VMware vSphere 7.0 and NetApp ONTAP 9.7, Page 61, Section: SAN boot LUN configuration on NetApp ONTAP. The guide states, "The WWPNs of the Cisco UCS B-Series server HBAs must be identified... The WWPNs are used to create initiator groups (igroups) on the NetApp controllers and for zoning on the Cisco Nexus switches." This highlights the WWPN as the primary identifier for troubleshooting zoning and connectivity.

3. NetApp ONTAP 9.8 SAN Configuration Guide, Section: FC configuration workflow, Step 4. The guide instructs to "Record the WWPNs of the FC ports on the host and the storage system. You will need these when you configure zoning on the FC switches." This confirms the WWPN is a fundamental component required for establishing and troubleshooting FC connectivity. A successful configuration results in the switch assigning an FCID.