ATTENTION: This is a work in progress and NOT read for use! It's currently unclear whether dracut even supports this mode of operation. See this discussion for more info.

dracut-rootoverlay

A simple dracut module that allows mounting a writable overlay over the (possibly read-only) root filesystem. Specifying rootoverlay=<device-spec> will cause the specified disk to be mounted as an overlay over whatever file system would be the root fs.

Be aware that the chosen overlay device must already contain a trivially mountable file-system with a work and upper folder for the overlayfs.

Requires systemd. Inspired from existing dracut modules 90dmsquash-live and 99-squash.