An example cloud-config for CoreOS

user-data

#cloud-config
 
coreos:
  etcd:
    # generate a new token for each unique cluster from https://discovery.etcd.io/new
    # WARNING: replace each time you 'vagrant destroy'
    discovery: https://discovery.etcd.io/c1b9507afe3f4f7c75430a138f5886c
    addr: $public_ipv4:4001
    peer-addr: $public_ipv4:7001
  etcd2:
    #generate a new token for each unique cluster from https://discovery.etcd.io/new
    discovery: https://discovery.etcd.io/c1b9507afe3f4f7c75430a138f5886c
    # multi-region and multi-cloud deployments need to use $public_ipv4
    advertise-client-urls: http://$public_ipv4:2379
    initial-advertise-peer-urls: http://$private_ipv4:2380
    # listen on both the official ports and the legacy ports
    # legacy ports can be omitted if your application doesn't depend on them
    listen-client-urls: http://0.0.0.0:2379,http://0.0.0.0:4001
    listen-peer-urls: http://$private_ipv4:2380,http://$private_ipv4:7001
  fleet:
    public-ip: $public_ipv4
  flannel:
    interface: $public_ipv4
  units:
    - name: etcd.service
      command: start
    # To use etcd2, comment out the above service and uncomment these
    # Note: this requires a release that contains etcd2
    #- name: etcd2.service
    #  command: start
    - name: fleet.service
      command: start
    - name: docker-tcp.socket
      command: start
      enable: true
      content: |
        [Unit]
        Description=Docker Socket for the API
 
        [Socket]
        ListenStream=2375
        Service=docker.service
        BindIPv6Only=both
 
        [Install]
        WantedBy=sockets.target