currently only very first part is written... ;)
first of all, install miniroot.
miniroot# udhcpc
miniroot# ip addr add 192.168.1.2/24 broadcast + dev eth0 miniroot# ip link set dev eth0 up miniroot# ip route add default via 192.168.1.1 miniroot# echo nameserver 192.168.1.1 > /etc/resolv.conf
replace 192.168.1.* with correct addresses for your network.
you can use any supported storage, partition, and (sub)directory.
e.g. make ext4 file system on first partition of external SD card, then mount it on /mnt
miniroot# mkfs.ext4 -E nodiscard /dev/mmcblk0p1 miniroot# mount /dev/mmcblk0p1 /mnt
ubuntu-core is minimal root file system. you can setup desktop or server environment after install.
miniroot# wget -P /mnt http://cdimage.ubuntu.com/ubuntu-core/releases/trusty/release/ubuntu-core-14.04.3-core-armhf.tar.gz
extract tarball (e.g. under "ubuntu" directory on external SD card)
miniroot# mkdir /mnt/ubuntu miniroot# tar -xpzf /mnt/ubuntu-core-14.04.3-core-armhf.tar.gz -C /mnt/ubuntu
setup sources.list
miniroot# wget -P /mnt/ubuntu/etc/apt http://files.androtab.info/radxa/ubuntu/sources.list
setup hostname (e.g. "ubuntu")
miniroot# echo ubuntu > /mnt/ubuntu/etc/hostname miniroot# sed -e 's/miniroot/ubuntu/' < /etc/hosts > /mnt/ubuntu/etc/hosts
setup serial console (automatically log-in as "root")
miniroot# sed -e 's/tty1/ttyFIQ0/g' -e '/^exec/c exec /sbin/getty -a root -L 115200 ttyFIQ0 vt100' < /mnt/ubuntu/etc/init/tty1.conf > /mnt/ubuntu/etc/init/ttyFIQ0.conf
if you cannot use serial console, you must setup user account here. (e.g. user "ubuntu" password "ubuntu")
miniroot# chroot /mnt/ubuntu useradd -G sudo -m -s /bin/bash ubuntu miniroot# echo ubuntu:ubuntu | chroot /mnt/ubuntu chpasswd
miniroot# boot /mnt:/ubuntu
you can specify path of root device in 1st argument if it's not mounted. (e.g. "boot /dev/mmcblk0p1:/ubuntu")
setup network (e.g. DHCP)
root@ubuntu:~# echo auto eth0 > /etc/network/interfaces.d/eth0 root@ubuntu:~# echo iface eth0 inet dhcp >> /etc/network/interfaces.d/eth0 root@ubuntu:~# ln -fs ../run/resolvconf/resolv.conf /etc/resolv.conf root@ubuntu:~# ifup eth0
update packages
root@ubuntu:~# apt-get update root@ubuntu:~# apt-get dist-upgrade
reboot
root@ubuntu:~# reboot
change miniroot configuration
miniroot# editenv
boot=/dev/mmcblk0p1:/ubuntu init=/sbin/init autoboot=1
miniroot# saveenv miniroot# reboot -f
root@ubuntu:~# apt-get install lubuntu-desktop
(TBD)