Heres the documentation about having multiple cidr pools in one cluster with the Cilium network driver, and it seems to imply that each Pod only gets one IP.

https://docs.cilium.io/en/stable/network/concepts/ipam/multi-pool/

There's something called Multus that I haven't looked into, but even then it looks like that is for multiple interfaces per Pod, not multiple IPS per interface.

https://github.com/k8snetworkplumbingwg/multus-cni

Containers are just network namespaces on Linux, and all the routing is done in iptables or ebpf, so it's theoretically possible to have multiple IP addresses, but doesn't look like anybody has started implementing it. There's actually a lot of Kubernetes clusters that just use stateful IPv6 NAT for the internal Pod network, unfortunately.

[–] Thiakil@aussie.zone 2 points 5 months ago

Weird! Though I guess a lot of these would be sitting behind load balancers / reverse proxies anyway (so ipv4 is fine) and unlikely to up and change isps very often? Lol

If I had to, I'd be trying to add an extra cidr to one of the options listed at https://kubernetes.io/docs/concepts/services-networking/dual-stack/#configure-ipv4-ipv6-dual-stack But as you say, probably doesn't work!