Linux installs (apart from grub boot blocks and partitioning) are JBOF (just a bunch of files).<p>Mostly, the non-user parts are &#x2F;etc &#x2F;boot &#x2F;usr and &#x2F;var (for package management), and things aren&#x27;t always in the same places and conf files may vary in options because of version&#x2F;patch differences.<p>Using symlinks and seperate directories, it&#x27;s theoretically possible to switch OSes at boot time assuming everything is symlink-agonistic (stow for operating systems)<p>It&#x27;s possible and rarely necessary except for personal playgrounds but a production box would follow 12factors standards and lifecycle the entire OS by switching the underlying base image with something like unionfs + hypervisor.<p>Lots of ways to shoot yourself in the feet, and in box rebuilds it&#x27;s usually much faster to just start fresh and deploy using configuration management than try to hammer a bank into the shape of plane.<p>Definitely make verified backups before attempting a lobotomy on anything real.