One of the attendees of our Building Next-Generation Data Center online course submitted a picture-perfect solution to scalable layer-2 fabric design challenge:
- VXLAN/EVPN based data center fabric;
- IGP within the fabric;
- EBGP with the WAN edge routers because they’re run by a totally different team and they want to have a policy enforcement point between the two;
- EVPN over IBGP within the fabric;
- EVPN over EBGP between the fabric and WAN edge routers.
The only seemingly weird decision he made: he decided to run the EVPN EBGP session between loopback interfaces of core switches (used as BGP route reflectors) and WAN edge routers.
Thanks to (see source)