[olug] Kernel Building

[William E. Kempf]

I run a Gentoo system these days.  Like it a lot better than the other
distros I've tried (RedHat, Mandrake, Lycoris) for numerous reasons.  One
of the big ones is that since everything is done "from source" it's forced
me to learn a LOT more about how Linux operates and how to configure it. 
Unfortunately, there's one dark area that I still struggle with, which is
Kernel building.  It's proving to be just a pain.

I had 1.4 kernels working some time ago following nothing but the install
guides and using genkernel.  Quite stable, which gave me a false sense of
accomplishment ;).  However, I have actual need for NPTL support so, have
had to migrate to the 2.6 kernels.  This is where my troubles start.

I started down this path in the very early days, and genkernel (for those
not running Gentoo, this is a script that automates kernel building for
Gentoo) was in flux and not really usable for 2.6.  So, I managed to get a
kernel that mostly worked by doing things by hand.  By mostly work, I mean
that all my programs/servers appear to run with out issue, but there are
errors at boot time (mostly, I believe, issues with devfs).

I want to learn how to handle this, but there are a few things standing in
my way, so I'm hoping someone can help me out.  First, is there any way to
read all of the messages sent to the terminal during a boot?  I'm aware of
both /var/log/messages and dmesg, but neither of these seem to be
complete, and are certainly not the exact same output seen during boot. 
This is making it difficult to diagnose issues for me.

Second, is there any way to test a kernel remotely?  It's not always
possible for me to be at the physical terminal when I'm administering the
box, for numerous reasons.  I do most everything remotely via ssh, but
testing the kernel this way is problematic.  Rebooting, if the kernel
doesn't boot properly, renders it impossible to recover remotely.  Seems
there should be a way to test this remotely, even if it's in an emulated
environment.

Finally, I'd appreciate any pointers to good documentation on this subject.

Thanks,

-- 
William E. Kempf
wekempf at cox.net