I mentioned in my recent post about running Asterisk on a $20/month Linode that I would try to follow up with a review of the steps necessary to actually get it working. This isn't going to be a detailed review, but just a more or less bulleted list of steps to take.

In the previous post I said that I had run into a kernel-package bug (#508487) that was preventing me from successfully building a Xen kernel with make-kpkg. So I installed the version from unstable, in which the bug had been fixed. This step may not be necessary at some point:

vi /etc/apt/sources.lst

[change deb-src to point to an unstable repository]

apt-get update

mkdir kernel-package && cd kernel-package

apt-get source kernel-package

apt-get build-dep kernel-package

dpkg-buildpackage -rfakeroot -uc -b

dpkg -i kernel-package_12.025_all.deb

Now to build the kernel.

cd /usr/src

apt-get source linux-image-uname -r

cd linux-2.6-2.6.26

aptitude install linux-patch-debian-2.6.26

/usr/src/kernel-patches/all/2.6.26/apply/debian -a amd64 -f xen

make menuconfig

[ Processor type & features -> Timer frequency - > 1000 HZ ]

make-kpkg clean

make-kpkg --initrd kernel_image

[wait a good while for the kernel to compile]

mv /lib/modules/2.6.26/kernel/ /root/kernel.old.old

dpkg -i ../linux-xen0-2.6.26_2.6.26-10.00.Custom_amd64.deb

update-initramfs -c -k 2.6.26

Now to build the Zaptel (DAHDI) kernel modules. It would normally be just a few steps, but there were some other problems regarding references to the RTC in zaptel-sources. You can find more information about this at the voip-info.org wiki, most relevantly under the heading " zaptel and xen-kernel 2.6.26-1-xen-686 in Debian Lenny ":

apt-get install zaptel-source

cd /usr/src

vi modules/zaptel/kernel/ztdummy.c

[comment out _#define USERTC lines]

m-a prepare

m-a build zaptel

m-a install zaptel

modprobe ztdummy

I think those are the basic steps I took. The actual path was much less clean, as I hit bugs and went back and forth. It's possible I have missed a step or two in there, or that the way I went about things wasn't right, ideal or even correct. Of course, all of this also presupposes that you have already configured your Linode to boot from a custom local kernel instead of the default Linode kernel. Instructions on how to do this can be found at at linode.com.