IP Prefix Route -Floating IP Overlay Index Use Case

RFC 9136 introduced the EVPN Route Type 5 (RT-5), an IP prefix route that supports recursive lookup resolution through Overlay Indexes. RFC 9136 presents four use cases, of which we tested the "Floating IP Overlay Index" use case. This use case is designed for a Tenant System using a floating IP as the gateway IP for the subnet behind it. The RT-5 performs recursive lookups and uses the floating IP as the next hop from the control plane. When the tenant subnet moves within the same Bridge Domain (BD), the RT-5 maintains the IP-VRF unchanged, while the RT-2 only updates the MAC-VRF associated with the floating IP.

In our testing, we conducted two runs. The floating IP and subnet were behind the Arista in the first run. We sent unidirectional unicast packets from sources behind H3C and Nokia to the floating IP and subnet behind Arista. No packet loss was observed during this test. Due to time constraints, we only verified unidirectional traffic from Nokia and H3C to Arista.

We moved the floating IP and subnet from Arista to H3C in the second run. We then sent unidirectional unicast packets from sources behind Arista to the floating IP and subnet behind H3C. Again, no packet loss was observed. As in the first run, only unidirectional traffic was verified from Arista to H3C.

Spirent TestCenter was used as the traffic generator for this test.