DTLS load balancing for CoAP

[lulf]

Load balancing for DTLS over UDP requires that UDP packets from the same IP is routed to the same pod which was used for the initial handshake. The default Kubernetes kube-proxy setting is round robin. It is also possible to configure kube-proxy in different modes, using IPVS (See https://kubernetes.io/blog/2018/07/09/ipvs-based-in-cluster-load-balancing-deep-dive/)

This is however not supported by OpenShift. An alternative is to leave this up to the user of cloud provider load balancer-specific configuration.