N9K Change the vPC Role
Currently the switch 1 takes the vPC secondary role with priority 15 while switch 2 takes the vPC primary role with priority 10. I switch their priority but their role doesn’t change.
1. Use Role Preempt (No-Disruptive)
N95K-01(config)# vpc domain 50
N95K-01(config-vpc-domain)# vpc role preempt
ERROR: Couldn’t perform role change: vpc 100 interface Po100 compact check failed.
Please address the inconsistency and try again
However, if there is configuration inconsistency, it won’t do the role preempt. I have mtu 9216 configured on Po100 while the primary vPC doesn’t have it. After I remove the additional configuration, it works.
N95K-01(config-vpc-domain)# vpc role preempt
Please ensure peer-switch is enabled and operational(‘show spanning-tree summary’).
Continue (yes/no)? [no] yes
N95K-01(config-vpc-domain)# show vpc | in role
vPC role : primary
vpc role preempt is not saved in the running-config.
2. Flap vPC Peerlink (Disruptive)
I shut and unshut the peerlink Po12 from the secondary vPC switch.
First, the peerlink is down. But the role is still primary and the vPC Po100 is still up.
N95K-01(config-if)# show vpc
vPC domain id : 50
Peer status : peer link is down
vPC keep-alive status : peer is alive
……
vPC role : primary
……
vPC Peer-link status
———————————————————————
id Port Status Active vlans
— —- —— ————————————————-
1 Po12 down –
vPC status
—————————————————————————-
Id Port Status Consistency Reason Active vlans
— ———— —— ———– —— —————
100 Po100 up success success 1,10,20
After that, peerlink is back and vPC role changed to secondary. The vPC Po100 is down.
N95K-01(config-if)# show vpc
vPC domain id : 50
Peer status : peer adjacency formed ok
vPC keep-alive status : peer is alive
…..
vPC role : secondary
…..
vPC Peer-link status
———————————————————————
id Port Status Active vlans
— —- —— ————————————————-
1 Po12 up 1,10,20
vPC status
—————————————————————————-
Id Port Status Consistency Reason Active vlans
— ———— —— ———– —— —————
100 Po100 down* success success
Finally, all the status restored with only role changed.