LinuxSoftware

Coding and tramping in Aotearoa / New Zealand

/etc/rwtab

Readonly root support.

This was add to Fedora for Stateless Linux, i.e. for creating live Fedora CDs.

How to use:

  • Edit /etc/sysconfig/readonly-root. Set 'READONLY' to 'yes'.
  • Add any exceptions that need to be writable that aren't in the stock /etc/rwtab to an /etc/rwtab.d file. (See below)

How it works:

  • On boot, we mount a tmpfs (by default, at /var/lib/stateless/writable), and then parse /etc/rwtab and /etc/rwtab.d/* for things to put there.

These files have the format: 

<type>  <path>
  • Types are as follows:
    • empty: An empty path. Example:

      • empty     /tmp

    • dirs: A directory tree that is copied, empty. Example:

      • dirs      /var/run

    • files: A file or directory tree that is copied intact. Example:

      • files     /etc/resolv.conf

A stock rwtab is shipped with common things that need mounted.