I don’t remember exactly where I heard about it (although I seem to remember that it was on the Ubuntu UK Podcast). andLinux is a package based on coLinux (Cooperative Linux), which in turn is a port of the Linux kernel to the Windows platform. How does that work? The short (and somewhat inaccurate) description is: the Linux kernel is run as a separate process under Windows, with a special set of drivers that tunnel I/O to a set of simulated devices (for example the hard disk read/writes are tunneled to a file, the network packets are sent to a virtual NIC, etc). What andLinux brings to the table is a set of preconfigured interoperability services (like installing Xming and setting up shortcuts to connect to the VM).

Some things I found during the short time I’ve run andLinux:

• latency is quite bad, especially in the case of GUI applications tunneled trough Xming. This is in a way understandable, since it is just one process, and inside of it there is an other set of “scheduling” (that is, it can’t take advantage of the multi-core systems)
• the supplied ubuntu version is rather old (7.10), but you can’t really upgrade because the kernel might break on you (see the above explanation about coLinux on why you need a special kernel). However, you can still update the packages, by editing /etc/apt/sources.list and using the name old-releases.ubuntu.com (see this thread on their forum). After the changes you can apt-get update / apt-get upgrade to your hearts content.
• Surprisingly aptitude is not installed, but this can be resolved quickly by apt-get aptitude
• to expand the size of the root drive, do the following (I’m assuming that you have cygwin installed)
  1. Stop coLinux
  2. Execute the following command on the main drive: dd if=/dev/null of=base.drv bs=1G seek=8 This will extend it to 8GB. Be aware that you have to use a filesystem which supports files larger than 2G (ie. NTFS) (credit to the OpenWRT wiki for inspiring the command)
  3. Restart coLinux and issue the following command (found it here): resize2fs /dev/cobd0 (found it here)
  4. Done! (BTW, isn’t is amazing that you can resize the FS online, without unmounting it first?)

PS. Other ways to run Ubuntu in parallel with Windows are: using Qemu or even using Qemu from a USB stick. And lets not forget the ubercool wubi installer, which makes installing Ubuntu on a Windows machine as easy as any other (Windows) program.