In Cisco UCS, a VSAN, also known as a named VSAN, creates a connection to a specific external SAN. The VSAN isolates traffic to that external SAN, including broadcast traffic. The traffic on one VSAN knows that the traffic on another VSAN exists but cannot read or access that traffic.
The name that you assign to a VSAN ID adds a layer of abstraction that allows you to globally update all servers associated with service profiles that use the VSAN. You do not need to reconfigure the servers individually to maintain communication with the external SAN. You can create more than one named VSAN with the same VSAN ID.
For more information about VSANs in Cisco UCS, including guidelines and recommendations, see the Cisco UCS Manager configuration guides.
Named VSANs in Cluster Configurations
In a cluster configuration, a VSAN can be configured to be accessible only to the Fibre Channel uplink ports on one fabric interconnect or to the Fibre Channel uplink ports on both fabric interconnects.
Named VSANs and the FCoE VLAN ID
Configure each VSAN with an FCoE VLAN ID. This property determines which VLAN is used for transporting the VSAN and its Fibre Channel packets.
For FIP-capable, converged network adapters, such as the Cisco UCS CNA M72KR-Q and the Cisco UCS CNA M72KR-E, the VSAN must be configured with a VLAN that is not the native VLAN for the FCoE VLAN ID. This configuration ensures that FCoE traffic can pass through these adapters.
In the following sample configuration, a service profile with a vNIC and vHBA mapped to fabric A is associated with a server that has FIP capable, converged network adapters:
The vNIC is configured to use VLAN 10.
VLAN 10 is also designated as the native VLAN for the vNIC.
The vHBA is configured to use VSAN 2.
Therefore, VSAN 2 cannot be configured with VLAN 10 as the FCoE VLAN ID. VSAN 2 can be mapped to any other VLAN configured on fabric A.
Creating a VSAN
Fibre Channel over Ethernet (FCoE) VLANs in the SAN cloud and VLANs in the LAN cloud must have different IDs. Using the same ID for an FCoE VLAN in a VSAN and a VLAN results in a critical fault and traffic disruption for all vNICs and uplink ports using that FCoE VLAN. Ethernet traffic is dropped on any VLAN that has an ID that overlaps with an FCoE VLAN ID.
On Compute page, choose the pod that includes the Cisco UCS Manager account.
On the Add VSAN screen, complete the following fields:
If you plan to use this VSAN for Fibre Channel zoning, see Configuring a VSAN for Fibre Channel Zoning.