Please note, this is an old blog post from several years ago. It may contain out of date information. If you spot anything broken or missing, please file a bug.
Asterisk on a $20/mo. Linode, part 2.
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 USE_RTC 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.