Comment 7 for bug 1752711

=== Abridged SRU verification ===h
NOTE: Xenial didn't publish an SRU regression per cloud-init 17.2.35, it still is on 17.1.46 which properly processes user-data.

# Xenial

root@publishing:~# gcloud compute instances create xenial-sru-test --zone=us-central1-b --image daily-ubuntu-1604-xenial-v20180224 --image-project ubuntu-os-cloud-devel --metadata-from-file user-data=sethostname.yaml
Created [https://www.googleapis.com/compute/v1/projects/cloud-init-testing/zones/us-central1-b/instances/xenial-sru-test].
NAME ZONE MACHINE_TYPE PREEMPTIBLE INTERNAL_IP EXTERNAL_IP STATUS
xenial-sru-test us-central1-b n1-standard-1 10.128.0.2 35.184.113.47 RUNNING
root@publishing:~# gcloud compute ssh xenial-sru-test
No zone specified. Using zone [us-central1-b] for instance: [xenial-sru-test].
Warning: Permanently added 'compute.2904988054415753140' (ECDSA) to the list of known hosts.
Enter passphrase for key '/root/.ssh/google_compute_engine':
Welcome to Ubuntu 16.04.4 LTS (GNU/Linux 4.13.0-1011-gcp x86_64)

 * Documentation: https://help.ubuntu.com
 * Management: https://landscape.canonical.com
 * Support: https://ubuntu.com/advantage

  Get cloud support with Ubuntu Advantage Cloud Guest:
    http://www.ubuntu.com/business/services/cloud

0 packages can be updated.
0 updates are security updates.

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

root@SRU-worked:~# dpkg-query --show cloud-init
cloud-init 17.1-46-g7acc9e68-0ubuntu1~16.04.1
root@SRU-worked:~# hostname xenial-sru-test # set it back so we can validate upgrade
root@SRU-worked:~# exit
logout
Connection to 35.184.113.47 closed.
root@publishing:~# gcloud compute ssh xenial-sru-test
... # Validating hostname presented in PS1
Last login: Fri Mar 2 16:55:23 2018 from 67.174.121.94
root@xenial-sru-test:~# rel=$(lsb_release -sc);
root@xenial-sru-test:~# line=$(awk '$1 == "deb" && $2 ~ /ubuntu.com/ {
> printf("%s %s %s-proposed main universe\n", $1, $2, rel); exit(0) };
> ' "rel=$rel" /etc/apt/sources.list);
root@xenial-sru-test:~# echo "$line" | sudo tee /etc/apt/sources.list.d/proposed.list
deb http://us-central1.gce.archive.ubuntu.com/ubuntu/ xenial-proposed main universe
root@xenial-sru-test:~# sudo apt-get update -q;
Hit:1 http://us-central1.gce.archive.ubuntu.com/ubuntu xenial InRelease
Get:2 http://us-central1.gce.archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]
Get:3 http://us-central1.gce.archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]
Get:4 http://us-central1.gce.archive.ubuntu.com/ubuntu xenial-proposed InRelease [253 kB]
...
Reading package lists...
root@xenial-sru-test:~# sudo apt-get install cloud-init;
...
The following packages will be upgraded:
  cloud-init
...
Setting up cloud-init (17.2-35-gf576b2a2-0ubuntu1~16.04.2) ...
root@xenial-sru-test:~# # Clean cloud-init artifacts so cloud-init runs against fresh instance
root@xenial-sru-test:~# sudo cloud-init clean --reboot --logs
Connection to 35.184.113.47 closed by remote host.
Connection to 35.184.113.47 closed.
ERROR: (gcloud.compute.ssh) [/usr/bin/ssh] exited with return code [255].
root@publishing:~# gcloud compute ssh xenial-sru-test
No zone specified. Using zone [us-central1-b] for instance: [xenial-sru-test].
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
...
Welcome to Ubuntu 16.04.4 LTS (GNU/Linux 4.13.0-1011-gcp x86_64)

 * Documentation: https://help.ubuntu.com
 * Management: https://landscape.canonical.com
 * Support: https://ubuntu.com/advantage

  Get cloud support with Ubuntu Advantage Cloud Guest:
    http://www.ubuntu.com/business/services/cloud

26 packages can be updated.
3 updates are security updates.

Last login: Fri Mar 2 17:07:00 2018 from 67.174.121.94
root@SRU-worked:~# # Note hostname properly updated
root@SRU-worked:~# dpkg-query --show cloud-init
cloud-init 17.2-35-gf576b2a2-0ubuntu1~16.04.2
root@SRU-worked:~# cloud-init status --long
status: done
time: Fri, 02 Mar 2018 17:13:08 +0000
detail:
DataSourceGCE
root@SRU-worked:~# grep Trace /var/log/cloud-init.log # No traces
# user-data b64encoded values present in instance-data.json
root@SRU-worked:~# grep user-data /run/cloud-init/instance-data.json
  "ds/user-data"
   "instance-data": "{\"user-data\":\"#cloud-config\\nhostname: SRU-worked\\n\"}",
  "user-data": "I2Nsb3VkLWNvbmZpZwpob3N0bmFtZTogU1JVLXdvcmtlZAo=",
=
root@SRU-worked:~# grep CODE /etc/os-release
VERSION_CODENAME=xenial
UBUNTU_CODENAME=xenial
root@SRU-worked:~#