Cisco Nexus 7000 Design Manual page 47

FlexPod Implementation and Design
Figure 21 FlexPod Discrete Uplink Design - Cisco VM-FEX Focus
The Cisco Fabric Extender technology provides both static and dynamic vNICs. As illustrated in this
example, vmk0, vmk1 and vmk2 are static adapters presented to the VMware vSphere environment.
Static vNICA and vNICB are assigned to the VM-FEX distributed virtual switch while Fabric A and B
static vHBAs provide SAN A and B connectivity for block based storage access. From a VMware ESXi
host perspective the vNICs and vHBAs are PCIe devices and do not require any special consideration or
configuration. As shown the Cisco UCS vNIC construct equates to a VMware virtual network interface
card (vmnic) and is identified as such.
Dynamic vNICs are allocated to virtual machines and removed as the VM reaches the end of its lifecycle.
Figure 21 details a dynamic vNIC associated with a particular VM. From a vSphere perspective the VM
is assigned to the VM-FEX DVS on port 1725. This port maps to two VIFs, 32774, which are essentially
an active/standby pair defined on Fabric A and B. The red line indicates the current active fabric path in
this example B. The Cisco UCS Manager allows administrators to assign a preferred active path (A or
VMware vSphere 5.1 on FlexPod with Nexus 7000 Using FCoE
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