during the system boot, an aufs (or unionfs) layer on top of the read-only mounted filesystem (squashfs) is established. any write you do will result in a transparent ramdisk overlay.
ok this is what is not working for me
no not live-helper i think it use live initramfs it create what is called a nfsroot this is a debootstrapped image that must be run. perhaps i should make something to this image to make it work with the ramdisk overlay. It would be because it use live-initramsfs without the part to make the ro image work with the rest of the live scripts ...I tried to make one live system to work with FAI but it complain that /var is read only so i am a little lost to debug this.i've no clue about fai. what did you exactely do? are you using live-helper?
So i need to read more on live-helper but all i found on the web was very scarce (read docs with FIXME everywhere ;) ). back at googling then thanks for pointing me here i think this is the part i miss.
regards, Jean.