Hi,
For general VXLAN, MP-BGP, EVPN etc., then the VXLAN Network with MP-BGP EVPN Control Plane white paper is quite good with designs and configuration examples.
There's also a bunch of presentations on Cisco Live. Take a look at BRKDCT-3378 - Building Data Center Networks with Overlays (VXLAN/EVPN & FabricPath) and BRKDCT-2404 - VXLAN Deployment Models - A practical perspective.
While the aforementioned will give you some good material, they focus mainly on the building of Clos based leaf-spine fabric for connectivity within a single data centre. And there's a reason for that.
Cisco are not proposing MP-BGP and EVPN as a data centre interconnect at this stage as all the required features are not yet implemented. Note in particular slide 108 in the BRKDCT-3378 presentation.
Taken from that slide:
VXLAN applicability evolves as the Control Plane evolves!
- Yesterday: VXLAN, yet another Overlay
- Data-Plane only (Multicast based Flood & Learn)
- Today: VXLAN for the creation of scalable DC Fabrics – Intra-DC
- Control-Plane, active VTEP discovery, Multicast and Unicast (Head-End Replication)
- Future: VXLAN for DCI – Inter-DC
- DCI Enhancements (ARP caching/suppress, Multi-Homing, Failure Domain isolation, Loop Protection etc.)
If you're watching the presentation the discussion around this is approximately 1hr. 20mins. in.
You might want to go back to your Cisco rep and go through what you're proposing and get their view on it's applicability and risk.
Regards