I took the Single-Attach demo of Git for EVPN (https://github.com/CumulusNetworks/cldemo-evpn
) to explore inter-subnet routing. This demo is not setup for hosts in different subnets to communicate so I added SVI's and advertised them into BGP. From a layer 3 perspective routing seems optimal, but I am concerned about the potential for sub-optimal forwarding.
For example, if all four leaf switches are advertising the same /24 network into the L3 routing domain then from an L3 perspective all paths seem equal and viable. If traffic is forwarded to the "wrong" leaf then it can figure out where to send it from its L2 domain information, but it traverses the fabric a second time.
I have seen Juniper and Cisco offer some ways to overcome this in their equivalent solutions. Does Cumulus also have features to ensure optimal routing/forwarding occurs between subnets? And if so, what option is available?