h1 $ ip addr show eth0 | grep 'inet '
    inet 10.194.12.221/20 brd 10.194.15.255 scope global eth0
h1 $ docker run -d swarm join --addr=10.194.12.221:2375 token://$CLUSTER_ID
9bf2db849bac7b33201d6d258187bd14132b74909c72912e5f135b3a4a7f4e51
h1 $ docker run swarm list token://$CLUSTER_ID
10.194.12.221:2375
h1 $ curl https://discovery-stage.hub.docker.com/v1/clusters/$CLUSTER_ID
["10.194.12.221:2375"]
