Single sided VPC configuration Example

Below is the single side VPC configuration example. In the below example 7Ks are configured in VPC so that downstream switch i.e 5K will believe that it is connected to only one upstream switch.

Note:- VPC configuration will only be done on the 7Ks not on the 5K as for 5K it is just a normal port channel.

As we know to create VPC we need two type of connectivity as mentioned below:-

1.VPC peer-link

VPC peer-link can only be configured on the layer-2 port-channel containing Ten-gig links. It cannot be configured on physical interfaces. For complete redundancy we should chose interfaces from different modules and must contain more than one interface.

VPC peer-link command is used to convert the port-channel to peer-link.

2.VPC peer-keepalive link

VPC peer-keepalive link is a L3 interface and it is just a backup to the peer-link but it will not pass any user traffic. Only hello packets are exchange over keepalive link. There is no impact if the peer-keepalive link is down and peer-link is up.

VPC peer-keepalive link can be configured using management interface or any L3 interface in default or any other VRF. Cisco recommends to use a dedicated vrf for peer keepalaive link.

N7K-1:-

Step1:- Enable Feature VPC

N7K-1(config)# feature vpc

Step 2:- Enable Feature LACP

N7K-1(config)# feature lacp

Step 3:- Create VPC domain. Make sure it is same on the VPC peer otherwise VPC will remain in down state.

N7K-1(config-if-range)# vpc domain 100 N7K-1(config-vpc-domain)# peer-keepalive destination 10.1.1.72 --<< Mgmt IP of N7K-2 Note:  --------:: Management VRF will be used as the default VRF ::--------

We get the below output if domain Id are different on peers switches.

N7K-1(config)# show vpc brief Legend:                 (*) - local vPC is down, forwarding via vPC peer-link vPC domain id                     : 100 Peer status                       : peer link not configured vPC keep-alive status             : peer is alive, but domain IDs do not match  -----<<<<<<<<<<<<<< Configuration consistency status  : failed Per-vlan consistency status       : failed Configuration inconsistency reason: vPC peer-link does not exist Type-2 consistency status         : failed Type-2 inconsistency reason       : vPC peer-link does not exist vPC role                          : none established Number of vPCs configured         : 0 Peer Gateway                      : Disabled Dual-active excluded VLANs        : - Graceful Consistency Check        : Disabled (due to peer configuration) Auto-recovery status              : Disabled

We get below output when peer switches are reachable via peer keepalive link.

N7K-1(config-vpc-domain)# show vpc brief Legend:                 (*) - local vPC is down, forwarding via vPC peer-link vPC domain id                     : 100 Peer status                       : peer link not configured -<< vPC keep-alive status             : peer is alive  -----<<< Configuration consistency status  : failed Per-vlan consistency status       : failed Configuration inconsistency reason: vPC peer-link does not exist  ---<<<<<<<<< Type-2 consistency status         : failed Type-2 inconsistency reason       : vPC peer-link does not exist vPC role                          : none established Number of vPCs configured         : 0 Peer Gateway                      : Disabled Dual-active excluded VLANs        : - Graceful Consistency Check        : Disabled (due to peer configuration) Auto-recovery status              : Disabled

Step 4:- Create port-channel for vpc peer-link. As soon as VPC PEER-LINK command is configured on

port channel the port type is changed to network and bridge assurance is enabled on the port-channel.

N7K-1(config)# int eth1/1-2 N7K-1(config-if-range)# channel-group 1 mode active N7K-1(config-if-range)# no shut N7K-1(config-if-range)# int po1 N7K-1(config-if)# switchport mode trunk N7K-1(config-if)# vpc peer-link Please note that spanning tree port type is changed to "network" port type on vPC peer-link. This will enable spanning tree Bridge Assurance on vPC peer-link provided the STP Bridge Assurance (which is enabled by default) is not disabled. N7K-1(config-if)# no shut

Step 5:- Configure port-channel connected to 5K.

N7K-1(config)# int eth1/3 N7K-1(config-if-range)# channel-group 10 mode active N7K-1(config-if-range)# no shut N7K-1(config-if-range)# int po10 N7K-1(config-if)# switchport mode trunk N7K-1(config-if)#vpc10

N7K-2:-

Step 6:- Enable vpc and lacp feature

N7K-2(config)# feature vpc N7K-2(config)# feature lacp

Step7:- Configure VPC Domain and vpc peer-keepalive link.

N7K-2(config-if-range)# vpc domain 100 N7K-2(config-vpc-domain)# peer-keepalive destination 10.1.1.71 --<< Mgmt IP of N7K-1 Note:  --------:: Management VRF will be used as the default VRF ::--------

Step8:- Configure VPC peer-link

N7K-2(config)# int eth1/1-2 N7K-2(config-if-range)# channel-group 1 mode active N7K-2(config-if-range)# no shut N7K-2(config-if-range)# int po1 N7K-2(config-if)# switchport mode trunk N7K-2(config-if)# vpc peer-link Please note that spanning tree port type is changed to "network" port type on vPC peer-link. This will enable spanning tree Bridge Assurance on vPC peer-link provided the STP Bridge Assurance (which is enabled by default) is not disabled. N7K-2(config-if)# no shut

Step9:- Configure vpc port-channel connected to N5k

N7K-2(config)# int eth1/3 N7K-2(config-if-range)# channel-group 10 mode active N7K-2(config-if-range)# no shut N7K-2(config-if-range)# int po10 N7K-2(config-if)# switchport mode trunk N7K-2(config-if)#vpc10

N5K-1:-

Step10:- Enable LACP feature

N5K-1(config)# feature lacp

Step 11:- Configure port-channel connected to 7Ks.

N7K-2(config)# int eth1/1-2 N7K-2(config-if-range)# channel-group 1 mode active N7K-2(config-if-range)# no shut N7K-2(config-if-range)# int po1 N7K-2(config-if)# switchport mode trunk

Note: - There is no need to configure VPC on 5K. As for 5K it just another port channel going to uplink switch.

Verification:-

VPC peering is up when both side peer-link and keepalive links are up as shown below.

N7K-1(config-if)# show vpc brief Legend:                 (*) - local vPC is down, forwarding via vPC peer-link vPC domain id                     : 100 Peer status                       : peer adjacency formed ok vPC keep-alive status             : peer is alive Configuration consistency status  : success Per-vlan consistency status       : success Type-2 inconsistency reason       : Consistency Check Not Performed vPC role                          : primary Number of vPCs configured         : 0 Peer Gateway                      : Disabled Dual-active excluded VLANs        : - Graceful Consistency Check        : Enabled Auto-recovery status              : Disabled vPC Peer-link status --------------------------------------------------------------------- id   Port   Status Active vlans --   ----   ------ -------------------------------------------------- 1    Po1    up     1

VPC can be verified using show vpc role command. ROLE PRIORITY command under VPC domain can be used to change the VPC role but bouncing of VPC peer link is required to apply the new configured priority.

N7K-1(config-if)# show vpc role vPC Role status ---------------------------------------------------- vPC role                        : primary Dual Active Detection Status    : 0 vPC system-mac                  : 00:23:04:ee:be:64 vPC system-priority             : 32667 vPC local system-mac            : 00:26:98:0d:3c:c4 vPC local role-priority         : 32667

Below command can show the status of the peer-keepalive link and its statistics.

N7K-1(config-if)# show vpc peer-keepalive vPC keep-alive status             : peer is alive --Peer is alive for             : (8525) seconds, (220) msec --Send status                   : Success --Last send at                  : 2014.12.19 17:55:30 978 ms --Sent on interface             : mgmt0 --Receive status                : Success --Last receive at               : 2014.12.19 17:55:30 978 ms --Received on interface         : mgmt0 --Last update from peer         : (0) seconds, (139) msec vPC Keep-alive parameters --Destination                   : 10.1.1.72 --Keepalive interval            : 1000 msec --Keepalive timeout             : 5 seconds --Keepalive hold timeout        : 3 seconds --Keepalive vrf                 : management --Keepalive udp port            : 3200 --Keepalive tos                 : 192

Below command shows the consistency check between the VPC peers. Peer with Consistency type-1 are not allowed to make pair.

N7K-1(config-if)# show vpc consistency-parameters global     Legend:         Type 1 : vPC will be suspended in case of mismatch Name                        Type  Local Value            Peer Value -------------               ----  ---------------------- ----------------------- STP Mode                    1     Rapid-PVST             Rapid-PVST STP Disabled                1     None                   None STP MST Region Name         1     ""                     "" STP MST Region Revision     1     0                      0 STP MST Region Instance to  1  VLAN Mapping STP Loopguard               1     Disabled               Disabled STP Bridge Assurance        1     Enabled                Enabled STP Port Type, Edge         1     Normal, Disabled,      Normal, Disabled, BPDUFilter, Edge BPDUGuard        Disabled               Disabled STP MST Simulate PVST       1     Enabled                Enabled Allowed VLANs               -     1                      1 Local suspended VLANs       -     -                      -

Particular vpc port-channel consistency parameter can also been seen using below command.

N7K.;-1(config-if)# show vpc consistency-parameters interface po10     Legend:         Type 1 : vPC will be suspended in case of mismatch Name                        Type                      Local Value                                Peer Value -------------               ----  ---------------------- ----------------------- STP Port Type               1                         Default                                       Default STP Port Guard              1                        None                                          None STP MST Simulate PVST       1                Default                                       Default lag-id                      1                                 [(7f9b,                                         [(7f9b,                                                             0-23-4-ee-be-64, 800a,                   0-23-4-ee-be-64, 800a,                                                             0, 0), (8000,                                       0, 0), (8000,                                                              0-5-73-ca-90-1, 13, 0,                    0-5-73-ca-90-1, 13, 0,                                                                       0)]                                             0)] mode                        1                                 active                                       active Speed                       1                                10 Gb/s                                       10 Gb/s Duplex                      1                                 full                                             full Port Mode                   1                            trunk                                           trunk Native Vlan                 1                                 1                                             1 MTU                         1                               1500                                          1500 Allowed VLANs               -                     1-4094                                          1-4094 Local suspended VLANs       -                     -                                                   -