I am running a Cisco 9k spine (2 No.) Leaf(20 No.) architecture. Its completely a MP- BGP EVPN VXLAN design. My concern is with integration of External Routing nodes(router and firewall) for WAN. I want this connectivity at spine instead of Border leaf.
Is this architecture is acceptable ?
What are the concern if I go with this design?
Thanks in advance
Yes you can its called Border Gateway on Spine (BGW on spine). Its supported in DCNM as well (latest couple of versions at least).
Border Gateways are used for L2 extension or extending your fabric to another fabric. Doesn't seem this is what there looking for.
I'd heavily advise against this. You should keep the spines as simple as possible. If you try and connect anything besides your leafs to the spines, now you have to create the VRFs on your Spines and additional BGP config, etc, etc. Yuck!
I'd recommend if you have a core that your border leafs are connected to, connect there or better yet - a wan services L3 switch pair that are connected to the core.