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Grub! Grub! Grub!

As of now I only use Grub as a bootloader for Linux. Bootloaders are among these things that do their work quietly in the background and which you miss when they are gone. The bootloader is loaded as first program from a harddrive at a computer's boot up. It then knows where the linux kernel resides, ie. the first partition of the first drive, with the second partition being the root partition. If you have your hard drive on the first IDE channel, you will probably never have to think about the boot loader.

Problems arise due to slightly more exotic configurations, such as when the kernel resides on a RAID-Array or an SCSI drive, attached to a seperate controller. The BIOSes I know usually assume that the first drive on the first channel is the most important one, with everything else following behind. If I attach another hard drive or an USB device such as a stick or drive, the order of devices gets messed up. On the next boot up, LILO halts with a pitiful LI, because everything has moved. Similar things can happen due to errors that happened when compiling or installing a new kernel.

Grub, and that is the great thing, has it's own little shell. Every defined entry can be changed at bootup time, to reflect a change in configuration or to fix errors. The system then will boot without further problems, so I can continue to work and then define the final, correct configuration. Even more serious mistakes, like forgetting to even give grub a list of available kernels, can be solved. I just need to look for my hard drive and kernel, and off I go.

Indeed, a wonderful program.

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