Document read-only/writable-ephemeral/writable-persistent directories

[jimmykarily]

We need to update the documentation with the paths of all the directories that mounted as persisted (this list).

There are directories that are:

• read only
• writable but ephemeral
• writable and persistent

users should be able to tell directory is which by reading our docs.

At least this page needs to be updated: https://kairos.io/docs/architecture/immutable/

Original Slack thread: https://spectrocloudcommunity.slack.com/archives/C04B1833NEA/p1705020000107159

[mauromorales]

@jimmykarily Not sure how soon we will address this, but might be worth copying the content of the discussion since it's ephemeral 🤣

[jimmykarily]

Well the essence of it is:

However we noticed that /var/lib is writable and persistent. i.e. new files and their changes persist after reboot.
Is this a mistake in the docs or a bug in Kairos or what?

We just need to document which paths are writable and persisted and which not.