I’m debugging a Cloud-Config user data script. It’d be nice to make changes and re-run, without rebooting, if that’s possible?

Here’s me doing it wrong:

#cloud-config

runcmd:
  - date >> /var/log/runcmd.log

After the instance boots, /var/log/cloud-init.log has:

Running module runcmd
[...]
finish: modules-config/config-runcmd: SUCCESS: config-runcmd ran successfully

and runcmd.log has one entry – so far, so good. Goal #1 is to add a second entry.

cloud-init init seems to only run vendor data. The internet says to first run cloud-init clean. This seems to delete my user data.

cloud-init single --name runcmd --frequency always writes the script out, but never runs it:

Cloud-init v. 19.1-1-gbaa47854-0ubuntu1~18.04.1 running 'single'
[...]
Writing to /var/lib/cloud/instances/152272562/scripts/runcmd - wb: [700] 38 bytes
Reading from /proc/uptime (quiet=False)
Read 14 bytes from /proc/uptime
cloud-init mode 'single' took 0.198 seconds (0.20)

I beleive the semaphore file is ignored ignored with --frequency always. Removing the semaphore file didn’t help.

If I reach goal #1, the second is to edit the user data – will Cloud-Config read from /var/lib/cloud/instance/user-data.txt, or is this just an artifact?