The first step that you should make is to you to choose which version of Asterisk you want to install.When you know which version you want to install download the according packages.

Note that we will install also libpri and zaptel packages. They are optional for Asterisk but if you want to use Asterisk with MeetMe (see MeetMe application and meetme.conf) or to use MusicOnHold you'll have to install zaptel. The TDMoE cards will also need the zaptel module in order to work correctly. If you will use PRI cards you'll have to install libpri module.

For Asterisk 1.2:

For Asterisk 1.4:


Now check the exact version of your kernel. You can achieve this by typing `uname -a`. The output should be something like this: `Linux luser 2.6.17-1.2142_EL #1 Tue Jul 11 22:41:14 EDT 2006 i686 i686 i386 GNU/Linux`. Check if you are using 2.6 or 2.4 kernel. Notice that. We'll need this info later. You should check if you have installed the kernel sources (for the current version of the kernel) on your machine. To achieve this type `rpm -q kernel-devel` The output of the screen should be something like this:


Note that if you don't have kernel sources you should install them. You can use yum again: `yum install kernel-devel`. If you use this command yum will install the sources for your current version of the kernel.

It is time to check for the availability of some other packages:
If any of those packages are not installed install them by using yum
If yum is unable to find one or more of these packages, try your luck with PBone. You should find the required packages there. When you download them, install them with either of those:

CentOS doesn't install the kernel sources into the /usr/src/linux directory as is written in Zaptel's and Asterisk's Makefile. Go to `/usr/src` and create a link named 'linux' to your kernel sources directory (the default place for your kernel's sources is /usr/src/kernels/...). The result should look like this:


Now extract the downloaded sources by the command `tar -vxzf PACKAGE.tar.gz`, where PACKAGE.tar.gz are the packages that we downloaded (libpri, zaptel and asterisk itself).

Installing Libpri:
Installing Zaptel:
Installing Asterisk:

In order to verify the asterisk installation start your asterisk daemon by typing `safe_asterisk` and connect to its console by typing `asterisk -vvvvvr`. Now reload the entire configuration by typing `reload`.