Tiny Core Linux

Tiny Core Linux is a minimal Linux distribution, designed for on-demand software loading. This page describes builds of Tiny Core Linux for the OLPC XO. For more information on Tiny Core Linux, see http://tinycorelinux.com

People involved:

• James Cameron,
• Yioryos Asprobounitis,
• George Hunt and;
• Jerry Vonau.

Core 4.7.7 2013-06-25

Announcing a build of Tiny Core Linux for OLPC XO.

Useful for testing and diagnosis without touching the internal storage.

Features

• runs on XO-1, XO-1.5, XO-1.75, or XO-4,

• configured for a single root shell in text mode, with alternate consoles available for login,

• based on Core 4.7.7, uses the OLPC kernel from 13.2.0-8, and includes latest signed Open Firmware versions for automatic upgrade,

• includes wireless firmware for each laptop, and wireless tools from Tiny Core Linux.

Downloads

• core-4.7.7-xo-2013-06-25.zip (49 MB) (md5sum 3ad809ddb06fefa75b7c3c8a28520d11)

Prepare USB Drive

• select a USB drive of at least 128 MB capacity, (it may have either a FAT or ext2 filesystem),

Linux - GNOME and Firefox

• insert the USB drive,

• click on the zip file link above, and a dialog window will appear asking you what you want done with the download,

• accept the default to open it in Archive Manager, and the Archive Manager window will appear,

• click on Extract, and a dialog window will appear asking you where to extract to,

• click on the USB drive in the Places list, then click on the Extract button, a dialog window will appear to tell you it worked,

• close the dialog window,

• close the Archive Manager window,

• close the Downloads window,

• eject the USB drive.

Linux - Terminal

• download the zip file using the link above, to the USB drive:

cd /run/media/olpc/FRED
wget ${URL}

• extract the zip file, at the top of the USB drive:

cd /run/media/olpc/FRED
unzip core-4.7.7-xo-2013-06-25.zip

• delete the zip file if you like, it is not required further,

rm core-4.7.7-xo-2013-06-25.zip

• eject the USB drive:

umount /run/media/olpc/FRED

Mac OS X

• insert the USB drive,
• control-click on the link above, select Download Linked File As ..., and a Save As dialog will appear,
• change Where to the name of the USB drive, usually Untitled, then click on Save, the dialog will go away,
• switch tasks to Finder, display the USB drive,
• double-click on the zip file, and the contents will be expanded, a new folder boot will be created,
• delete the zip file if you like, it is not required further,
• eject the USB drive.

Windows

• download the zip file,
• insert the USB drive,
• use WinZip or other operating system features to expand it onto the USB drive,
• eject the USB drive.

Prepare laptop

• ensure the laptop is unsecured, or sign the kernel and initrd files with your deployment keys,
• insert the USB drive into the laptop,

Boot laptop

• turn on the laptop, and the USB drive will be automatically read,
• after a short wait you will see the Tiny Core Linux system prompt:

root@box:~# 

• you may remove the USB drive.

Tiny Core Linux is now ready for your commands.

Configure wireless

• identify the wireless adapter interface name:

iw dev

• expected values vary:

laptop	adapter	kernel modules	interface name
XO-1	Marvell 8388	libertas usb8xxx	wlan0
XO-1.5, XO-1.75, XO-4	Marvell 8686	libertas libertas_sdio	wlan0
XO-4	Marvell 8787	mwifiex mwifiex_sdio	mlan0

• scan for networks:

iw dev mlan0 scan

• associate with an open network:

iw dev mlan0 connect network

• configure the interface using DHCP:

udhcpc -i mlan0

Configure wired USB ethernet after boot

• insert USB ethernet adapter,
• configure the interface using DHCP

udhcpc

Installing additional utilities

• additional utilities needed for a task can be installed:

su -c 'tce-load -wi rsync' tc

See the Tiny Core Linux documentation for more detail.

Additional shells

• additional shells can be started using Alt/F2, username tc.

Access to XO-1 filesystem

• you can mount and investigate the XO's JFFS2 flash filesystem, for example:

cat /proc/mtd
mkdir /mnt/root
mount -t jffs2 mtd0 /mnt/root

Access to XO-1.5, XO-1.75 and XO-4 filesystem

• you can mount and investigate the XO's eMMC or microSD filesystems, for example:

cat /proc/partitions
mkdir /mnt/boot /mnt/root
mount /dev/mmcblk0p2 /mnt/boot
mount /dev/mmcblk0p2 /mnt/root

Backup and Restore

See Backup for how to use Tiny Core Linux for backup and restore of a laptop.

Reversion

See Reversion for how to use Tiny Core Linux to revert an XO with OLPC OS to a pristine filesystem configuration, as if it had just been installed. This can be used to quickly clean a set of class specific or loaned laptops.

Remote Diagnosis

• connect a USB ethernet adapter or configure wireless,
• load the OpenSSH extension:

su -c 'tce-load -wi openssh' tc

• configure OpenSSH server with defaults:

cd /usr/local/etc/ssh && cp sshd_config.example sshd_config

• start the OpenSSH server:

/usr/local/etc/init.d/openssh start

• wait for new host keys to be generated,
• change the password for the user tc:

passwd tc

• find the IP address of the laptop:

ifconfig

• set up inbound port forwarding on router if required,
• connect your OpenSSH client,

ssh tc@$IP

See also remote diagnosis using firmware only.

Boot from JFFS2 on XO-1

Mount the JFFS2 filesystem, save the original boot directory, and make a new one:

mkdir /mnt/root
mount -t jffs2 mtd0 /mnt/root
mv /mnt/root/boot /mnt/root/boot.orig
mkdir /mnt/root/boot

Mount the USB drive, and copy the required files to the JFFS2 filesystem:

mount /dev/sda1 /mnt/sda1
cp /mnt/sda1/boot/olpc.fth /mnt/root/boot/
cp /mnt/sda1/boot/initrd.x86 /mnt/root/boot/
cp /mnt/sda1/boot/vmlinuz.0 /mnt/root/boot/

Release the filesystems, remove the USB drive, and reboot:

umount /mnt/sda1
umount /mnt/root
reboot

References

• Tiny Core Linux http://www.tinycorelinux.com/
• mktinycorexo script http://dev.laptop.org/~quozl/mktinycorexo/
• mktinycorexo script git repository git clone http://dev.laptop.org/~quozl/mktinycorexo/.git