Re-write load-balancer to take advantage of know control-plane members

[thebsdbox]

At the moment with the change to leaderElection we're mainly focussed on just providing VIP services. It would be good to investigate if we can grab all controlPlane members regularly and use this as the backend array for load-balancing.

[dhawal55]

Would it be possible to forward traffic received at the VIP to the Kubernetes service IP? Kube-proxy can that take care of load balancing to all API server instances

[thebsdbox]

This is for the control-plane, the TCP traffic for the load-balancers is out of cluster so would never go to the kube-proxy

[dhawal55]

yes, I'm talking about the control plane. Once the traffic reaches the VIP (which is a kube-vip pod running on controlPlane node), we can have an ip-table rule forward the traffic to the internal kubernetes service IP.

[thebsdbox]

I'll build a cluster over the coming days and see what I need to do

Notes:
https://stackoverflow.com/questions/60100233/k8s-forwarding-from-public-vip-to-clusterip-with-iptables

[thebsdbox]

Added with IPVS in #296