Boot your N800 Maemo SDK today with Amazon's EC2

I really appreciate that someone has created VMWare and QEMU images for running the Maemo SDK. Unfortunately, my machines, both Mac and PC, are typically too busy with other stuff to allow me to quickly fire-up a virtual machine image that will chew up all my computing resources. Instead, booting up a machine from Amazon for about $0.15/hour or so is affordable enough for my N800 development. No more downloading a 1.5+GB image; EC2 users can instead just share an image and a boot script and be up-and-running at a known-good starting point.

Of course, the first step was to get an EC2 (and S3) account. I waited almost a month for my EC2 account. At some point I'll figure some way to let other people just rent a machine from me to make it easy, but that'll require a bit of thought and management. For now, head on over to Amazon, request an account, and they'll get to you eventually. There isn't any monthly fee or hidden costs; you just pay for the time, bandwidth, and storage you use. As long as you copy your work off somewhere else, such as by using Subversion hosted by code.google.com, you can shutdown without having any recurring fees.

Once you have an EC2 and S3 account, you'll want to download the EC2 command-line tools and your access identifiers.

The next step was to choose the Linux image I wanted to use as my starting point. Personally, I'm a Gentoo fan because I think Linux has an excessive number of binary-compatible dependencies on the C library and Gentoo solves that by recompiling every new application, instead of needing to update your C library to match the binary-compatibility requirements of all your applications. Of course, that makes application installation slow and Maemo itself uses the Debian package model, so Debian or Ubuntu make the most sense. However, Amazon supplies some nice reference images on Fedora Core 4 that might simplify my life around issues like ssh login security when the root account password can't be secret. Nothing is easy, so I found an Ubuntu image that has reasonable documentation on how it was created such that someone could redo this all with a better supported AMI in the future.

At this point, the issues started to pile up and I decided my best hope was to document my steps in scripts so that I can reproduce them with a better starting image and make corrections that people point out to me. I decided to the Google Subversion server I mentioned earlier to host my script at http://code.google.com/p/maemo-sdk-image/.

I used a Mac to run my script, but I plan to eventually make it run on the N800 itself or on a Windows PC. Right now, the script uses bash, which isn't natively on either the N800 or Windows. Also, the Unix-style version of the EC2 command-line tools also utilizes bash. I think the solution for both is likely to install bash.

The access identifier information ended up placed in a subdirectory called 'secrets' under where I ran the script. These secrets end up getting copied temporarily to the EC2 images for the purpose of bundling them up. I exclude that directory from the bundle.

I say 'images', because I end up working with four different EC2 images in the script. The first one is the base Fedora Core image that Amazon makes public. The second one is a bare-bones Ubuntu Feisty image that can be boot on EC2. The third one is patched to be self-bundling. The fourth one actually contains the Maemo SDK. The third and fourth could easily be combined, but I am still inching along.

In theory, you can run all of the steps using 3 separate calls to the script:

  1. ./build_maemo_api build-feisty
  2. ./build_maemo_api patch-feisty
  3. ./build_maemo_api install-maemo
I think the first two should work reasonably well to create a self-bundling Ubuntu image, but I haven't run them exactly like that to test them out yet.

The third step certainly won't work. One issue is that the Nokia binaries require you to agree to a license, so you'll need to do that part manually. This also only gets you to version 3.1 of the SDK, so you'll need to update that as well. There are also several steps missing before the image is really usable, such as setting up the X server and VNC server to allow you to view the emulated N800 screen remotely.

Please feel free to post your comments here or on the wiki on how to improve the script. I won't hesitate to utilize your inputs on the script hosted on the Subversion server.

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