> On Feb 23, 2024, at 20:32, William Herrin <b...@herrin.us> wrote: > >> The relay server `dhcplb` could, maybe, help in that scenario >> (dhcplb runs on the anycast IP, the “real” DHCP servers on >> unicast IPs behind dhcplb). > > Although they used the word "anycast", they're just load balancing.
The idea is to run the relays on an anycasted IP (so the load balancer / relay IP is anycasted). > [….] Relying on ECMP for anycasted DHCP would be a disaster > during any sort of failure. Add or remove a single route from an ECMP > set and the hashed path selection changes for most of the connections. Consistent hashing (which I thought was widely supported now in ECMP implementations) and a bit of automation in how announcements are added can greatly mitigate this. Ask
