cloudinit.stages emits logs messages like the following when the cloudconfig module's distro attribute doesn't match the running disribution
When a cloudinit.config.cc*py module distros attribute doesn't match the discovered Distribution.name, cloudinit.stages emits a log message about skipping the module in the following form:
2017-09-07 06:03:25,838 - stages.py[INFO]: Skipping modules ['runcmd'] because they are not verified on distro 'ubuntu'. To run anyway, add them to 'unverified_modules' in config.
But, it doesn't actually skip running the module, we can see in the logging that follows:
Running module runcmd (<module 'cloudinit.config.cc_runcmd' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_runcmd.py'>) with frequency once-per-instance.
cloudinit.stages should honor a skipped module and avoid running its handler.
Might also look into unverified_modules behavior, it looks like it is ineffective as well. Just a log message and no further change in behavior made by run_section.