Troubleshoot EVPN VxLAN in Multi-site

[tawa-ndafa]

Hi, 

I am running the topology below with EVPN/VxLAN Multisite on dcloud. Unfortunatley the two hosts in different sites and different VNI could not ping each other. However same VNI different sites the can ping each other and also different VNI same site they can ping each other. 

So basically I had an issue with IRB between sites. The arp shows as incomplete when I check a host in a different site. I suspected the issue was on BUM traffic. I tried to follow the document below however, the document doesn't look right to me. 

 Is the config for BUM traffic correct?:

1. Configuration on BGW NVE interface - the site(leaf switches) are using multicast for  BUM traffic but the NVE interface on the BGW is configured to use "ingress replication bgp" 

My understanding is that BUM can be handled using static method (ingress replication) or dynamic(multicast) and the two can't be mixed with in a site. 

For BUM between sites we use ingress replication and the config is fine.

https://www.cisco.com/c/en/us/support/docs/multiprotocol-label-switching-mpls/mpls/215722-configure-and-verify-in-evpn-vxlan-multi.html

[M02@rt37]

Hello @tawa-ndafa,

In EVPN Multisite deployments, it's common to use ingress replication for BUM traffic between sites. This method ensures efficient forwarding of BUM traffic across different physical networks and provider boundaries.

The configuration on the BGW NVE interface should align with the chosen method of BUM traffic handling within and between sites. If you are using multicast-based replication within a site, then the NVE interfaces should be configured accordingly. If you are using ingress replication within the site and between sites, then the NVE interfaces should be configured with "ingress replication bgp".

[cj4mcse01 · Accepted solution]

interface nve1
  no shutdown
  host-reachability protocol bgp
  source-interface loopback1
  multisite border-gateway interface loopback100
  member vni 4000100
    suppress-arp
    multisite ingress-replication
    mcast-group 231.0.0.1
  member vni 4000200
    suppress-arp
    multisite ingress-replication
    mcast-group 231.0.0.2
  member vni 4000502 associate-vrf