Comment 16 for bug 1691489

Zesty verification:
 # Saw initial failure before upgrade
ubuntu@zesty1:~$ dpkg-query --show cloud-init
cloud-init 0.7.9-153-g16a7302f-0ubuntu1~17.04.2
ubuntu@zesty1:~$ grep reformat /var/log/cloud-init.log
2017-09-12 22:08:16,313 - DataSourceAzure.py[DEBUG]: reformattable=True: partition 1 (/dev/sdb1) on device /dev/disk/cloud/azure_resource was ntfs formatted and had no important files. Safe for reformatting.

# Saw 5 successes across reprovisions after upgrade

ubuntu@zesty1:~$ grep reformat /var/log/cloud-init.log 2017-09-12 22:19:39,881 - DataSourceAzure.py[DEBUG]: reformattable=False: partition 1 (/dev/sdb1) on device /dev/disk/cloud/azure_resource was not ntfs formatted
ubuntu@zesty1:~$ mount | grep mnt
/dev/sdb1 on /mnt type ext4 (rw,relatime,data=ordered)
ubuntu@zesty1:~$ dpkg-query --show cloud-init
cloud-init 0.7.9-233-ge586fe35-0ubuntu1~17.04.1
ubuntu@zesty1:~$ grep -i error /var/log/cloud-init* /run/cloud-init/*
grep: /run/cloud-init/dhclient.hooks: Is a directory
/run/cloud-init/result.json: "errors": []
/run/cloud-init/status.json: "errors": [],
/run/cloud-init/status.json: "errors": [],
/run/cloud-init/status.json: "errors": [],
/run/cloud-init/status.json: "errors": [],
ubuntu@zesty1:~$ cat /run/cloud-init/result.json
{
 "v1": {
  "datasource": "DataSourceAzure [seed=/var/lib/waagent]",
  "errors": []
 }
}