Comment 2 for bug 2003121

Agreed, automating this boot-time step seems ideal from an user experience and identity correctness perspective.

Resetting machine-id is currently expected to be done by the image builder at build time. Taking responsibility for this behavior at runtime carries risk that will need to be evaluated and mitigated prior to introduction. This would require all systemd services that use machine-id to be ordered after (or potentially restarted after, if already started) whichever cloud-init service would be responsible for this behavior.

If this behavior is expected to be default in upstream cloud-init, risk is multiplied across distros, since each distro may have different services and ordering.

Also note that resetting machine-id at runtime may cause a slower boot by forcing delayed ordering of services.