I can't mount external disk as root via overlayfs. I did everything from here.
config 'mount' option target '/overlay' option uuid '38424f05-e921-4311-9ac0-088800f57675' option enabled '1' option fstype 'ext4'
I mounted to '/', /tmp/root' too but got the same result
In dmesg the following messages:
[ 11.230915] mount_root: loading kmods from internal overlay [ 12.917015] mount_root: failed to mount -t jffs2 /dev/mtdblock9 /tmp/overlay: Invalid argument [ 14.074363] mount_root: switching to jffs2 overlay [ 14.079255] mount_root: switching to jffs2 failed - fallback to ramoverlay