udev for Gentoo
While installing a new kernel on my good old gentoo box, I disabled devfs to switch to udev. It turns out that /dev is completely empty on disk, and I guess it used to be configured to mount /dev as devfs on boot.
With udev, that mount happens in userspace from scripts, so init got sort of unhappy and complained that it couldn't open a console (no devices yet), and I couldn't see any of the boot process until udev was up and the console
I had to boot the gentoo CD, mount my root partition, and create a few bootstrap devices, in particular, the console.
/sbin/MAKEDEV console seemed to get all the tty's in place and all was well then. For good measure, I also created
/dev/null, since it looked like something had tried to write to it anyway.
I have the 220.127.116.11 kernel running now, pretty painlessly. You can really feel the speed increase on a p5-200!