docker_opts cloud config

cloud-config.yaml

#cloud-config

coreos:
  units:
    - name: docker.service
      command: restart
      content: |
        [Unit]
        Description=Docker Application Container Engine
        Documentation=http://docs.docker.com
        After=docker.socket early-docker.target network.target
        Requires=docker.socket early-docker.target

        [Service]
        Environment=TMPDIR=/var/tmp
        EnvironmentFile=-/etc/docker_opts.env
        EnvironmentFile=-/run/flannel_docker_opts.env
        MountFlags=slave
        LimitNOFILE=1048576
        LimitNPROC=1048576
        ExecStart=/usr/lib/coreos/dockerd --daemon --host=fd:// $DOCKER_OPTS $DOCKER_OPT_BIP $DOCKER_OPT_MTU $DOCKER_OPT_IPMASQ


write_files:
  - path: /etc/docker_opts.env
    permissions: 0644
    owner: core
    content: |
      DOCKER_OPTS="--log-level=warn --ip-forward=true --dns=172.21.128.5 --dns=172.21.128.6"
      DOCKER_OPT_BIP="--bridge=br0"
      DOCKER_OPT_MTU=
      DOCKER_OPT_IPMASQ=