Nexus vPC peer-link down and object tracking

[vsurresh]

Hi all.

I'm a little bit confused about vPC object tracking during peer-link down and looking for some advice. I'm referring to this article about object tracking https://networkrare.com/cisco-nexus-enhance-object-tracking-boolean-or-in-vpc/

As per Cisco guide - In a scenario when the vPC peer link goes down, the vPC secondary switch shuts down all of its vPC member ports if it can still receive keepalive messages from the vPC primary switch (which indicates that the vPC primary switch is still alive). The vPC primary switch keeps all of its interfaces up. 

Suppose I have object-tracking on both switches which monitors both the peer-links and an uplink. Let's say the vPC primary switch loses both uplink and peer-link so, the track will shut down all the vPC member ports on the primary switch. Because the peer-links are now down, the secondary vPC also shutdown the vPC ports right? Doesn't that mean all of the vPC ports are now down on both switches? What am I missing here? 

Thanks in advance

[MHM Cisco World]

thanks

[vsurresh · Accepted solution]

Looks like this blog has the right answer - https://adamraffe.com/nexus%207000/virtual%20port%20channel/2013/02/24/vpc-and-single-10ge-modules-what-you-should-know/

Essentially, vPC Object Tracking is a method of signalling that a switch has lost a linecard and that the other vPC peer should assume the primary role (thereby keeping all its own vPC member links up)