I have uploaded an A20 build of the Ubuntu 13.10 (Saucy Salamander) core distribution taken from here a couple of days ago: http://cdimage.ubuntu.com/ubuntu-core/daily/current and combined it with the latest 3.4.61 kernel+modules here: http://dl.cubieforums.com/patwood/A20-kernel-3.4.61.tar.gz. Edit: this image has been superseded by this one: http://dl.cubieforums.com/patwood/saucy-13.10-ct-cb2-3.4.75.img.xz
The download is here: http://dl.cubieforums.com/patwood/saucy-core-developer-20131013-A20-3.4.61.img.xz and is only 133MB; the 590MB root fs fits on a 1GB SD card. The file size is 138596052 bytes and the md5sum (compressed file) is c6ad3257237b6aa59725593b2e1e3d0e.
. It was created from the official 13.10 build for armhf from here: http://cdimage.ubuntu.com/ubuntu-core/releases/saucy/release/
and the 3.4.75+ kernel from here: http://dl.cubieforums.com/patwood/A20-kernel-3.4.75-ct.tar.gz
(the previous image was based on a pre-release build from about a week before). It supports both CB2 and CT dual-boot and has OTG, with g_ether loaded at startup. The file size is 128655692 bytes and the md5sum (compressed file) 335c481c71e915f1cd66e33ef0ec912d.Edit2: I have removed the saucy-core-developer-20131013-A20-3.4.61.img.xz due to problems with replacing the kernel on the ext4 root fs. Please use the newer image instead.
This is useful for headless servers and do-it-yourself image builders. apt-get is installed and updated, along with openssh, networking (including wireless), and developer tools. There's no GUI, but X and desktops can be installed with apt-get. HDMI console framebuffer and virtual terminals are supported. Note that if you want to use Mali, G2D, or CedarX, you should remove the extraargs settings in /boot/uEnv.txt; similarly, the HDMI settings are currently locked at 1280x720p60 in extraargs to support the widest array of monitors and TVs.
root password is root,
but the serial console and virtual terminal tty1 are automatically logged in as root
I've also made it easy to boot this system with the SD card mounted read-only, and various system dirs that need write access are mounted as ramdisks (e.g., /run, /tmp, /var/tmp, /var/cache, /etc). To enable this, copy /boot/uEnv-ro.txt over /boot/uEnv.txt; to switch back to writable SD, copy /boot/uEnv-rw.txt over /boot/uEnv.txt.
I've posted the mechanisms used here separately in the initrd.gz download.
Note: if you plan on deploying something based on this distro, make sure you disable ssh or generate a new set of ssh host keys:
ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key
Note: unlike a lot of distros, this one has only one partition. I've done away with the FAT32 boot partition; all the boot files (uImage, script.bin, uEnv.txt) live on the root partition in /boot.
I've gone back to a dual-partition layout, mostly because u-boot seems fussy about loading large files from ext4 file systems.