Comment 26 for bug 1611074

I've just uploaded this to zesty and to xenial-proposed.
The changes can be seen
  https://git.launchpad.net/cloud-init/commit/?id=9e904bbc3336b96475bfd00fb3bf1262ae4de49f

There was also a change made to packaging so that on upgrade we will update /etc/fstab
on the ephemeral disk to include
  x-systemd.requires=cloud-init.service,comment=cloudconfig

This fixes the upgrade, then resize case.
That change can be seen at
  https://git.launchpad.net/cloud-init/commit/?h=ubuntu/devel&id=fac7c5c3b5758c03b3df40ce25849c73de1a8140