USB booting and more

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I've always been curious about booting from USB devices. With most motherboards, the use of an external USB CD or DVD-ROM seems to be a no brainer.

As USB flash memories now offer up to several gigabytes of storage, it seems they might serve for many pursposes.

The guys behind Damn Small Linux think that it is a good idea to have a simple GNU/Linux setup that can boot from a credit card size CD-ROM or from a USB flash memory with only 50Megabytes!! I needed to try this out. I had most success using the USB-ZIP configuration on most of the BIOS on the systems I tried this out. I even have found a new life for that old 64MB USB 1.1 pendrive I bought several years ago. The system that includes a graphical environment, wordprocessor, Firefox browser, pdf reader, spreadsheet, xmms, vnc viewer, and a long list of other useful applications.

All that was quite an achivement, and the developers want to keep the system size small. One of the drawbacks is DSL is based on a 2.4 kernel, but they claim lots of device drivers are being backported.

Besides achieving to boot a system from a USB pendrive, I had a goal in my mind: Some of the systems I have developed over time are based on 1U rack PCs lacking of a CD-ROM or floppy drive. The system setup till now was based on plugging in a USB-based CD-ROM to load Knoppix Linux and then to run a script that will download the system's disk image over a network connection. It was fast and easy. However, with high capacity pendrives and the possibility of booting from the pendrive I thought that I could forget about the old system.

What I have working now is a 2GB pendrive holding DSL boot plus the compressed image of the system I want to install. The new routine for installing these 1U computers is:
  1. plug-in the pendrive
  2. power on the computer.
The computer will power itself down once the install is complete. The whole process takes less than seven minutes. I really think it is a very good way to install any OS on a batch of identical computers. (The problem with just writing down the OS to a batch of hard drives is that this does not allow you to test the hardware the disks will be installed on).

I recomend you to have a look at this setup system for any similar need. I guess that if your storage needs exceed existing pendrive's capacity you may use a USB-powered hard drive to achive the same result.

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