Hi Guys.
I have question regarding the vPC peer switch command under vpc domain :)
The purpose of this command is to allow secondary switch to also send BPDU instead of proxying BPDU to Primary vPC peer.
The Bridge ID sent within the BPDU has to be the same for both switch so Spanning-tree configuration must be the same on both switches.
What I did was to set the N5K vPC peer switches to Prio 0 for all vlan => Spanning-tree root for all vlan
spanning-tree vlan 1-3967,4048-4093 priority 0
The problem is that I had some inconsistencies over my Peer Link:
I can guarantee that the BID was the same for both switch but secondary peer switch was saying that its Root port was on vPC peer link .... On the other side the primary vPC peer said that the vPC peer link was in an inconsistent state ....
Here are the configs :
N5K-1
spanning-tree vlan 1-3967,4048-4093 priority 0
vpc domain 100
peer-switch
role priority 100
system-priority 100
peer-keepalive destination 10.2.8.174
interface port-channel1718
switchport mode trunk
spanning-tree port type network
speed 10000
vpc peer-link
interface Ethernet1/17
switchport mode trunk
channel-group 1718 mode active
interface Ethernet1/18
switchport mode trunk
channel-group 1718 mode active
N5K2
spanning-tree vlan 1-3967,4048-4093 priority 0
vpc domain 100
peer-switch
role priority 100
system-priority 100
peer-keepalive destination 10.2.8.173
interface port-channel1718
switchport mode trunk
spanning-tree port type network
speed 10000
vpc peer-link
interface Ethernet1/17
switchport mode trunk
channel-group 1718 mode active
interface Ethernet1/18
switchport mode trunk
channel-group 1718 mode active
Output from N5K-1
N5K-1(config)# sh spanning vlan 930
VLAN0930
Spanning tree enabled protocol rstp
Root ID Priority 930
Address 0023.04ee.be64
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 930 (priority 0 sys-id-ext 930)
Address 0023.04ee.be64
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Po1212 Desg FWD 1 128.5307 (vPC) Edge P2p
Po1718 Desg BKN*1 128.5813 (vPC peer-link) Network P2p *BA, vPC_PL_Inc
Eth1/15 Desg FWD 2 128.143 P2p
Eth1/16 Desg FWD 2 128.144 P2p
Output from N5K-2
N5K-2(config)# sh spanni vlan 930
VLAN0930
Spanning tree enabled protocol rstp
Root ID Priority 930
Address 0023.04ee.be64
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 930 (priority 0 sys-id-ext 930)
Address 0023.04ee.be64
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Po1212 Desg FWD 1 128.5307 (vPC) Edge P2p
Po1718 Root BKN*1 128.5813 (vPC peer-link) P2p *vPC_PL_Inc
Eth1/15 Desg FWD 2 128.143 P2p
Eth1/16 Desg FWD 1 128.144 P2p