The vPC peer link is the link used to synchronize states between the vPC peer devices. The vPC peer link carries control traffic between two vPC switches and also multicast, broadcast data traffic. In some link failure scenarios, it also carries unicast traffic. You should have at least two 10 Gigabit Ethernet interfaces for peer links. Contrast this to the Keepalive link which is more restricted to heartbeat type messages.

The only valid command listed here is show vpc brief as covered in my CBT Nuggets course.

The show vpc role command displays the peer status, role of the local device, vPC system MAC address and system priority, and MAC address and priority for the local vPC device.