Cisco Nexus 5000 Series Operation Manual page 19

Chapter 1 Virtual Port Channel Operations
vPC Failure Recovery
S e n d d o c u m e n t a t i o n c o m m e n t s t o n 5 k d o c f e e d b a c k @ c i s c o . c o m
Figure 1-1 vPC Response to a Member Port Failure
MAC_C
SW
N5k-1 N5k-2
Po1
vPC 2
MAC_A
vPC Peer Link Failure
Figure 1-2 shows the vPC response to a peer link failure. In a vPC topology, one vPC peer switch is
elected as the vPC primary switch and the other switch is elected as the vPC secondary switch, based on
the configured role priority for the switch. In the unlikely scenario where the vPC peer link goes down,
the vPC secondary switch shuts down all of its vPC member ports if it can still receive keepalive
messages from the vPC primary switch (which indicates that the vPC primary switch is still alive). The
vPC primary switch keeps all of its interfaces up. As a result, the hosts or switches that are connected to
the Cisco Nexus 5000 Series switch or Cisco Nexus 2000 Series Fabric Extender vPC pair redistributes
all the flows to the vPC member ports that are connected to the vPC primary switch.
As a best practice, we recommend that you configure a physical port channel that has at least two
10 Gigabit-Ethernet ports as the vPC peer link.
Cisco Nexus 5000 Series NX-OS Interfaces Operations Guide, Release 5.0(3)N2(1)
1-15