initrd.... what is it and why do I need it

[mychl]

I've been working on updating my kernel to 2.4.2. I followed the steps in the NHF. My old version 2.2.15-mdk??? from my drake 7.1 CD didn't have an initrd in lilo, I put one in for my new kernel, but I don't understand what it is. I'm having some trouble, so would like to know more......

Thanks

[3Wheels]

I can't give you all the details, but initrd is used on boot before the hard drive is accessible. It is used to create and INITial Ram Disk. That is, it builds a filesystem in RAM instead of on a hard drive, so it can do all its boot-up activities. Once it's booted to the point it can access and use the hard drive, it switches over. You should be able to do a "man initrd" or do web searches for something like "initrd AND RAM AND disk AND boot". You see initrd heavily used in embedded or floppy-based Linux system where there is no hard drive. For these systems, you compile RAM disk and initrd capabilities into the kernel.
HTH

[ 27 February 2001: Message edited by: mattmorrow ]