z2buntu Compiling Environment

The z2buntu rootfs contains working compiling tools, but the Zipit doesn't really have the processing power to compile programs in a reasonable amount of time. This is a good use for QEMU. QEMU can run the z2buntu rootfs as a virtual machine faster than the Zipit can run natively. I run Ubuntu Linux on my home desktop so this guide needs to be tweaked for whatever OS you run.

First you need a rootfs. you can download my z2buntu rootfs or create your own using this guide (make sure to use the jaunty distro). If you use the z2buntu rootfs, I would recommend increasing the size of the partition so that you have enough room to install the required packages and source codes you'll be compiling. To do this, write the image to an SD card (change the img filename and the device to suit your needs):

sudo dd if=/path/to/your-rootfs-filename.img of=/dev/YOURDEVICE

Using gparted, increase the partition size to your liking. Then, create a new image file:

sudo dd if=/dev/YOURDEVICE of=/path/to/your-new-z2buntu-qemu.img

You will need to install qemu to run the virtual machine. For Ubuntu it's as easy as
sudo apt-get install qemu-kvm qemu-kvm-extras

The last thing you need to get is a kernel for the emulator. Ubuntu provides a kernel at http://ports.ubuntu.com/dists/jaunty/main/installer-armel/current/images/versatile/netboot/vmlinuz-2.6.28-11-versatile.

Now it's time to start the emulator. Here's a minimal command line startup with 256M RAM and networking:
qemu-system-arm -M versatilepb -kernel vmlinuz-2.6.28-11-versatile -m 256 -hda z2buntu-qemu.img -append "root=/dev/sda1 rw" -net nic,vlan=0 -net user,vlan=0

For networking in the VM to work everytime at startup, edit /etc/network/interfaces and add:
auto eth0
iface eth0 inet dhcp

Now on to the fun stuff. You can install ssh and apache into the image, then setup port redirection. This allows you to forward, let say, port 2222 on your host computer to port 22 inside the VM. If you ssh to port 2222 on your host computer, it redirects you into the VM. I also redirect host port 8080 to 80 inside the VM allowing me to download directly. Redirection works by adding this to your qemu command line:
-redir tcp:2222::22 -redir tcp:8080::80

So, I can now ssh into my Zipit emulator from anywhere in the world, compile a program, compress it/create a deb, and put it up for download all inside the VM. Pretty amazing.