After upgrading a pair of Nexus-6k from 6.x code to 7.3(5)1 I’ve noticed a strange behavior where OSPF adjacency from Cisco ASA to Nexus was not forming over vPC peer link. All was working fine on 6.x code.
Took a bit to figure it out and this article helped to resolve this issue.
New command was introduced to support Layer 3 routing over vPC – “layer3 peer-router“. It is configured under VPC domain.
vpc domain X
peer-gateway
layer3 peer-router
Once I added it to both Nexuses OSPF adjacency came up on both ASAs. Keep in mind “peer-gateway” also needs to be present.
Below is a great reference table for Nexus model and code that supports this command.