title: cloud-init ignoring static IP network configuration
body: <p>I running the Ubuntu 18.04 cloud image and trying to configure networking through cloud-init.  For some reason it is ignoring my networking when I try to assign a static IP and just falls back to using DHCP.  I'm not sure why and I'm not sure how to debug it.  Does anyone know if I am doing something wrong or how I should further troubleshoot this:</p>
  
  <p>Here is my <code>config.yaml</code> I'm using to generate my <code>config.img</code>:</p>
  
  <pre><code>#cloud-config
  network:
      version: 2
      ethernets:
          ens2:
              dhcp4: false
              dhcp6: false
              addresses: [10.0.0.40/24]
              gateway4: 10.0.0.1
  password: secret # for the 'ubuntu' user in case we can't SSH in
  chpasswd: { expire: false }
  ssh_pwauth: true
  users:
      - default
      - name: brennan
        ssh_import_id: gh:brennancheung
        sudo: ALL=(ALL) NOPASSWD:ALL
  hostname: vm
  runcmd:
      - [ sh, -xc, "echo Here is the network config for your instance" ]
      - [ ip, a ]
  final_message: "Cloud init is done.  Woohoo!"
  </code></pre>
  
  <p>Everything else in the config seems to be working, it's as if it doesn't even see the <code>network</code> portion though.</p>
  
  <p>I'm attaching the <code>.img</code> as a <code>cdrom</code> to read the <code>cloud-init</code>.  You can see how I'm running it here: <a href="https://github.com/brennancheung/playbooks/blob/master/cloud-init-lab/Makefile" rel="noreferrer">https://github.com/brennancheung/playbooks/blob/master/cloud-init-lab/Makefile</a></p>
  
  <p>NOTE: Once I'm logged into the box I can replace the config in <code>/etc/netplan</code> with the <code>network</code> section above and re-apply it and the networking comes up fine with a static IP.  So I think there aren't any obvious errors that I am missing.  This leads me to believe it is related to the cloud-init networking module(s) and not <code>netplan</code> itself.</p>