Cisco Cisco Nexus 5010 Switch Guida Alla Progettazione

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agg(config)# vpc domain 1

agg1(config-vpc-domain)# role priority 100

agg2(config-vpc-domain)# role priority 110

There are no functional issues when the spanning-tree root and vPC primary node do not match. This can only

cause some suboptimal convergence time due to spanning-tree resynchronization when the peer link is flapped or

a vPC device is reloaded.

Because of this, in case you want to restore the original mapping between the spanning-tree root and vPC primary

device, you can follow this procedure on the secondary, operational primary device:

1. Enter the vPC domain configuration, vpc domain <domain_id> (same vPC domain you are using).

2. Reset the vPC role priority with the command vpc role priority <priority_number> (reentering the same

priority is all right).

3. Perform a shut-no shut operation over the peer link.

Alternatively, you can create a script (which you should customize):

7k-1(config)# cli alias name vpcpreempt conf t ; vpc domain <number> ; role
priority 32767 ; int po 10 ; shut ; no sh

7k-1(config)# show cli alias

CLI alias commands

==================

alias :show cli alias

vpcpreempt :conf t ; vpc domain 10 ; role priority 32767 ; int po 10 ; shut ;
no sh

vPC Peer Link

This PortChannel should be configured on dedicated-mode 10 Gigabit Ethernet interfaces across two different

10 Gigabit Ethernet line cards:

agg(config)# interface port-channel10

agg(config-if)# vpc peer-link

agg(config-if)# switchport trunk allowed vlan <all access vlans>

Configuration for Single 10 Gigabit Ethernet Card

Although it is possible to use a single 10 Gigabit Ethernet card on the Cisco Nexus 7000 Series for both core

connectivity and the peer link is possible, it is not the most desirable option. If you lose the 10 Gigabit Ethernet card

on the vPC primary, you lose not only core connectivity, but also the peer link. As a result, ports will be shut down

on the peer vPC device, isolating the servers completely.