Cisco Cisco Nexus 5010 Switch 设计指南
Design Guide
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agg1(config-if)# channel-group 51 mode active
agg1(config)#interface Port-channel 51
agg1(config-if)# switchport
agg1(config-if)# vpc 51
!
agg2(config)#interface ethernet2/9
agg2(config-if)# channel-group 51 mode active
agg2(config)#interface Port-channel 51
agg2(config-if)#switchport
agg2(config-if)# vpc 51
If the consistency check does not show success, you should verify the consistency parameters. Typical reasons that
a vPC may not form include the following:
●
The VLAN that is defined in the trunk does not exist, or it is not defined on the peer link
●
One member port is configured as the access and the other as the trunk
●
Mismatches exist in the VLANs that are carried on the trunk, etc
The following example shows how to verify that the vPC configuration is consistent between two vPC peers for the
global consistency parameter as well as for a specific PortChannel:
tc-nexus7k01-vdc2# show vpc consistency-parameters global
tc-nexus7k01-vdc2# show vpc consistency-parameters int port-channel 51
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
Allowed vLANs - 10-14,21-24,50,60 10-14,21-24,50,60
After a port is defined as part of a PortChannel, any additional configurations, such as activation or disablement of
Bridge Assurance or trunking mode, are performed in the interface PortChannel configuration mode. Trying to
configure spanning-tree properties for the physical interface instead of the PortChannel will result in an error
message.
LACP
You should use LACP for dynamic bundling of the ports in the vPC group, because LACP verifies that the ports being
bundled are actually part of the same physical or virtual switch, preventing erroneous configurations.
For example, if the PortChannel is configured as active on the Cisco Nexus 7000 Series Switch and the downstream
switch is not configured for PortChannel, the PortChannel ports will be shown as in the individual (I) state and will run
regular spanning tree.
After the access layer switches are configured for LACP, the negotiation completes the PortChannel forms:
tc-nexus5k01(config)# int eth2/1-2
tc-nexus5k01(config-if-range)# channel-group 51 mode passive