For once I feel a little out of touch after I took a bit of a break from following the news to focus on studying, and suddenly everyone is talking about immutable distributions. What are they exactly? What are the benefits and the disadvantages of immutable systems?
My understanding is that most immutable distributions store the root filesystem in a read-only partition separate from userspace. If you want to install something that would modify this partition, it is applied temporarily until reboot. On reboot, the operating system attempts to resolve your changes, and if they break something it will reject them.
Each OS might implement immutability differently, but I believe that’s the general idea. macOS is another example of an immutable operating system, as of Big Sur.
Read only root and was they way unix was installed for decades. Some things, like nfs roots, somewhat rely on it (multiple machines would run a single static install of unix, with user partitions being mounted on demand on each machine).
People don’t like dealing with partitions though so modern distros tend towards a single root paritition with everything in it. It’s funny to go back to the old way.
