Dynamic Routing Over vPC

[Yazeed Fataar]

Hi

I am struggling to understand whether it is possible or not to enable dynamic routing over vPC. I have searched and found the following statements (Sandeep Singh , Aug 2017)

• Enable Layer 3 routing between vPC peers over a separate layer 3 link.
• Do not enable routing over vPC for vPC members. In the DCI environment, use HSRP tracking to ensure Layer 3 failover between Data Center.

I have the following setup that I need vetting please. I have two Nexus 7000 switches with two VDCs (Core and Distribution). I need to run OSPF between CORE and DISTRIBUTION what is the best method and is it possible for me to utilise the Back to Back VPC to form OSPF peering?

Physical

Logical

Reference

Sandeep Singh (Aug 2017) "vPC Best Practices for Nexus 7000 and 5000" [Online] Available From: vPC Best Practices for Nexus 7000 and 5... - Cisco Support Community

Regards

Yazeed

[msanchez]

I had this same problem and am using a "similar" topology.  BGP sessions were not coming up on the 2nd device because of TTL decrement issue.  I just implemented a working config about an hour ago by upgrading NX-OS and adding the two command below to my vpc domain.  Hope it helps someone.

Upgraded to 7.2(2)D1(2)

vpc domain ##

layer3 peer-router     (Changes the TTL behavior of packets destined to the peer)

peer-gateway exclude-vlan ###  (It excludes the VLAN from the vpc peer )

[jjfaure]

Hi,

I need to use a similar network design with BGP, my question is:

Is it possible to activate an IBGP session between the 2 Nexus of vpc domain, having options you said (layer3 peer-router, peer-gateway exclude vlan x) ?  I can not check this cause i have no Nexus in our labs, please can you inform about?

Best Regards

[Darian O'Dirling - TCE]

Hi @Yazeed Fataar ,

I see you are working with layer 3 routing over vPC peers. I encourage anyone who is running into this issue or wants to learn more about layer 3 routing on Nexus switches to watch this video made by a colleague mind. This video discusses Layer 3 routing over vPC and the vPC enhancements needed to successfully create a routing adjacency over a vPC enabled vlan.

https://www.youtube.com/watch?v=q_xAZJpqRiM