t enable the vPC feature: (config)# feature vpc Before configuring anything else regarding vPCs, you must first establish a vPC domain. The domain number must match for all switches working with the configured vPCs: NX-5K-1(config-if)# vpc domain 1 Though it's not required, I have configured one side of the pair to be the master with the vpc role priority command. The switch that acts as the spanning tree root should be the master. A lower priority value wins. The default value is 32768: NX 5K-1(config-if)# role priority 1000 vPCs require a link between the vPC peer switches called a peer keepalive link. This link is in addition to the port channel between the switches in which the VLAN trunks reside. The peer keepalive link must be a routed link, in that an IP address is used on each side. The link can be over an existing IP network and, by default, Cisco suggests that it be established over the management interface. I'm not a huge fan of putting what amounts to critical (criticality is in the eye of the beholder) connections on the man- agement network, but this example shows how to do SO. The management VRF is used by default on a Nexus 5000: NX-5K-1(config-vpc)# peer-keepalive destination 10.10.10.2 Note: Management VRF will be used as the default VRF : On a Nexus 7000, this link can be any interface, since they all default to routing mode anyway. Here. I've configured e3/1 to be the peer keepalive link: NX-7K-1 (config)# int e3/1 NX-7K-1 (config-if)# ip address 10.255.255.1/24 NX-7K-1 (config)# vpc domain 1 NX-7K-1 (config-vpc-domain)# peer-keepalive destination 10.255.255.2 Now let's configure the other side of the link on 7K-2: NX-7K-2 (config)# int e3/1 NX-7K-2 (config-if)# ip address 10.255.255.2/24 Chapter 18: Cisco Nexus And the vPC peer keepalive: NX-7K-2 (config)# vpc domain 1 NX-7K-2 (config-vpc-domain)# peer-keepalive destination 10.255.255.1 vPC requires that a link-preferably a trunk-between the vPC peers be defined as a peer link. This link will be used for the traversal of traffic necessary to 