Portal Talk:MicroOS
This page could do with some more details about how to use a Rescue Disk specifically for MicroOS.
In particular you have to manually simulate the existence of /sysroot that the fstab assumes is present when mounting /etc (because it expects to run during initramfs only). Creating a symlink named /sysroot pointing to / before calling 'mount -a' is the only way the /etc gets successfully mounted, but then you have to clean it up again once you're done with the chroot and before rebooting back into the original system.