Network configuration for runtime clusters and clouds
A runtime cluster's nodes and a runtime cloud's runtime cloud clusters by default use a Multicast (UDP)-based protocol to manage clustering. Alternatively, aDocker runtime cluster's nodes and a Docker runtime cloud's runtime cloud clusters by default use a Unicast (TCP)-based protocol to manage clustering.
There are a variety of network-related issues you might encounter.
The runtime cluster and runtime cloud use JGroups to implement the clustering support.
