Boot DSL from USB - A small deviation from the irregular schedule

I have been annoyed by the lack of a decent description of getting Linux to boot from a USB stick, specifically DSL and DSL-N. Oh, I know there are descriptions, but by "decent" I mean a full description that allows me to extrapolate for my specific needs, not just a simple recipe. So after having finally sat down to read some more documentation I finally understood how to do it and solved a few problems along the way. Since I have many more important things to do I am naturally escaping those by writing down parts of it - and yes, that will probably mean another meaningless recipe but the goal is to at least bring up the gotchas that I encountered, hopefully someone will find it useful.

To begin I had a 512MB stick with DSL 2.something and since DSL3.0.1 is out, as well as DSL-N 0.1RC4, and I was itching to try them both out. Obviously I could have made it easy for myself by ordering a stick with DSL already on it, but I've never liked doing it the easiest way. Oh, and I plan on making a donation instead but so far I've just toyed with DSL, and I need to find the time to figure out how to work properly with it, notably compile my own apps (myDSL isn't as up-to-date as I'd like) and of course actually find a scenario where I really use DSL. Currently, booting from a USB stick and even embedded on my work computer using QEMU is just something that's cool and fun :-)

I got DSL2 on the USB stick by booting Knoppix 4 and downloading a "usb creation" script from the ibiblio mirror (can't find it now though). This gave me a version which could both boot directly and which could be started from within windows so that was too cool I thought, especially since at that time my desktop machine broke (Shuttle SN45G suddenly refused to start, turned out to be the motherboard, possibly the BIOS chip) so I wanted to use my work laptop for other things than work and without the horrible overhead of a typical corporately managed machine. In addition the hard disk is encrypted so I couldn't easily resize the partition and install any OS on unused space.

Of course that worked fine. But this time I wanted to do it myself. The small recipes that I did find were brief so I figured it couldn't be too difficult, and this was correct. I am just the type of person who needs to understand a little bit more than just how to do something, namely why I'm doing it and what I am actually doing. Next post will be about what to do, why you do it (as far I understand at the moment) and some issues you may encounter along the way.