Awesome-O

I too was initially trying to use overlay-root in Debian and couldn't get it to work. Until I did a serial debug of the boot process. Here's what I found. Ubuntu has a built in executable called wait-for-root, which the overlay-root calls during boot. I believe the Debian port just used the Ubuntu code, but excluded the wait-for-root. There is no wait-for-root exe in Debian, hence why it was not configuring the overlay. Like @ValdikSS said you also require busybox-static package. (I left my /etc/initramfs-tools/initramfs.conf with BUSYBOX=auto) So I created my own wait-for-root script an placed it on the $PATH. (/usr/local/sbin) #!/bin/sh device=${1} timeout=${2} # [ "$timeout" = "0" ] && return 1 # wait-for-root writes fstype to stdout, redirect to null until [ -b $device ]; do echo "waiting for root device $dev" sleep $timeout done I worked out that the two parameters come from the overlay-fs, device and timeout. With that worked out I then created the overlay.local.conf, as per the instructions in /etc to overlay my NVME disk from the eMMC. (No need to edit overlay.conf) # # Overlay Root Config # NVME drive 0 partition 1 # overlayroot="device:dev=/dev/nvme0n1p1,recurse=0,timeout=5" You need to do an update-initramfs after to place the wait-for-root in the initrd. After a reboot I now have this: Caveats: You cannot do swap files/partitions in the /etc/fstab when overlayfs is activated, it will comment them out. If you're running docker it will not work with it's built in default overlay-fs. You will need to install the fuse-overlayfs package and create a custom docker config in /etc/docker/daemon.json Solutions: Create a swap systemd unit that starts after the overlay is active Create the unit file in /etc/systemd/system Name the file the same as the swap location. (In this case I named it dev-nvme0n1p2.swap, with dashes instead of /'s) [Unit] Description="Swap device (/dev/nvme0n1p2)" [Swap] What=/dev/nvme0n1p2 Options=defaults Priority=10 [Install] WantedBy=basic.target Docker Daemon needs this added to it: "storage-driver": "fuse-overlayfs",