Configuring Virtual Port Channels
vPC Number
Note You must ensure that the two switches connected by the vPC peer link have certain identical operational and configuration parameters.
When you configure the vPC peer link, the vPC peer switches negotiate that one of the connected switches is the primary switch and the other connected switch is the secondary switch. By default, the Cisco
You can also configure which of the vPC switches is the primary switch. If you want to configure the role priority again to make one vPC switch the primary switch, configure the role priority on both the primary and secondary vPC switches with the appropriate values, shut down the EtherChannel that is the vPC peer link on both switches by entering the shutdown command, and reenable the EtherChannel on both switches by entering the no shutdown command.
MAC addresses that are learned over vPC links are also synchronized between the peers.
Configuration information flows across the vPC peer links using the Cisco Fabric Services over Ethernet (CFSoE) protocol. All MAC addresses for those VLANs configured on both switches are synchronized between vPC peer switches. The software uses CFSoE for this synchronization.
If the vPC peer link fails, the software checks the status of the remote vPC peer switch using the
The software learns of a vPC peer switch failure when the keepalive messages are not returned over the
Use a separate link (vPC
vPC Number
Once you have created the vPC domain ID and the vPC peer link, you can create EtherChannels to attach the downstream switch to each vPC peer switch. That is, you create one single EtherChannel on the downstream switch with half of the ports to the primary vPC peer switch and the other half of the ports to the secondary peer switch.
On each vPC peer switch, you assign the same vPC number to the EtherChannel that connects to the downstream switch. You will experience minimal traffic disruption when you are creating vPCs. To simplify the configuration, you can assign the vPC ID number for each EtherChannel to be the same as the EtherChannel itself (that is, vPC ID 10 for EtherChannel 10).
Note The vPC number that you assign to the EtherChannel connecting to the downstream switch from the vPC peer switch must be identical on both vPC peer switches.
Cisco Nexus 5000 Series
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