Systemd dhcpd on CoreOS

#cloud-config

hostname: docker

coreos:
  units:
    - name: zz-default.network
      mask: true
    - name: systemd-networkd.service
      command: restart
    - name: dhcpcd-config.service
      command: start
      content: |
        [Unit]
        Description=Set dhcpcd config
        Before=dhcpcd.service
        [Service]
        Type=oneshot
        RemainAfterExit=yes
        ExecStart=/usr/bin/sh -c '/usr/bin/echo hostname > /etc/dhcpcd.conf'
        ExecStart=/usr/bin/sh -c '/usr/bin/echo option domain_name_servers, domain_name, domain_search, ntp_servers >> /etc/dhcpcd.conf'
    - name: dhcpcd.service
      command: restart