Double-Sided vPC
Double-Sided vPC
Dual-sided vPC or Double-side vPC as known as back-to-back vPC or multilayer vPC is combination of multiple vPC layers.
In double-sided vPC we have two layers of vPC pairs. Traditionally, our access layer switches are in vPC whose southbound links connect to servers. Their northbound links connect to aggregation layer who are also in vPC. To ensure that BPDUs and LAG IDs are unique, each vPC has to have different domain-id. You can configure the vPCs with same domain IP, but you must manually configure different system IDs for each vPC pair.
There is another use case for back-to-back vPC which is for Datacenters Interconnectivity. You can extend one Datacenter to another Datacenter without having full mesh connectivity between each layer. For Datacenter Interconnectivity, Cisco recommends that we have two MST regions one for each datacenter.
Double-sided vPC Workshop
In this workshop, we are going to demonstrate back-to-back vPC configuration in three different domains. With domain 1 being aggregation layer, domain 2 and 3 being access layer.
AGGR01
feature lacp feature vpc interface mgmt 0 ip address 192.168.1.1/24 exit vpc domain 1 peer-keepalive destination 192.168.1.2 source 192.168.1.1 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 1 mode active no shutdown interface port-channel 1 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/3-4 switchport switchport mode trunk channel-group 11 mode active no shutdown interface port-channel 11 switchport switchport mode trunk vpc 11 interface ethernet 1/5-6 switchport switchport mode trunk channel-group 12 mode active no shutdown interface port-channel 12 switchport switchport mode trunk vpc 12
AGGR02
feature lacp feature vpc interface mgmt 0 ip address 192.168.1.2/24 exit vpc domain 1 peer-keepalive destination 192.168.1.1 source 192.168.1.2 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 1 mode active no shutdown interface port-channel 1 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/3-4 switchport switchport mode trunk channel-group 11 mode active no shutdown interface port-channel 11 switchport switchport mode trunk vpc 11 interface ethernet 1/5-6 switchport switchport mode trunk channel-group 12 mode active no shutdown interface port-channel 12 switchport switchport mode trunk vpc 12
ACC01
feature lacp feature vpc interface mgmt 0 ip address 192.168.2.1/24 exit vpc domain 2 peer-keepalive destination 192.168.2.2 source 192.168.2.1 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 2 mode active no shutdown interface port-channel 2 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/3-4 switchport switchport mode trunk channel-group 11 mode active no shutdown interface port-channel 11 switchport switchport mode trunk no shutdown vpc 11
ACC02
feature lacp feature vpc interface mgmt 0 ip address 192.168.2.2/24 exit vpc domain 2 peer-keepalive destination 192.168.2.1 source 192.168.2.2 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 2 mode active no shutdown interface port-channel 2 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/3-4 switchport switchport mode trunk channel-group 11 mode active no shutdown interface port-channel 11 switchport switchport mode trunk no shutdown vpc 11
ACC03
feature lacp feature vpc interface mgmt 0 ip address 192.168.2.3/24 exit vpc domain 3 peer-keepalive destination 192.168.2.4 source 192.168.2.3 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 3 mode active no shutdown interface port-channel 3 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/5-6 switchport switchport mode trunk channel-group 12 mode active no shutdown interface port-channel 12 switchport switchport mode trunk no shutdown vpc 12
ACC04
feature lacp feature vpc interface mgmt 0 ip address 192.168.2.4/24 exit vpc domain 3 peer-keepalive destination 192.168.2.3 source 192.168.2.4 vrf management exit interface ethernet 1/1-2 switchport switchport mode trunk channel-group 3 mode active no shutdown interface port-channel 3 switchport switchport mode trunk no shutdown vpc peer-link interface ethernet 1/5-6 switchport switchport mode trunk channel-group 12 mode active no shutdown interface port-channel 12 switchport switchport mode trunk no shutdown vpc 12