When you provision a NetScaler CPX instance on a Docker host, the Docker engine creates a virtual interface, eth0, on the CPX instance. This eth0 interface is directly connected to a virtual interface (veth*) on the docker0 bridge. The Docker engine also assigns an IP address to the NetScaler CPX instance in the network 172.17.0.0/16.
Quelle: NetScaler CPX Express – Documentation and load balancing how-to guides