Note

The last version of Rocky Linux that this procedure was tested on was version 8.5. Because the bulk of this procedure relies on source builds directly from Asterisk and a simple set of Development Tools from Rocky Linux, it should work on all versions. If you run into a problem, please let us know!

Installing Asterisk on Rocky Linux¶

What is Asterisk?

Asterisk is an open source framework for building communications applications. Additionally, Asterisk turns an ordinary computer into a communications server, as well as powering IP PBX systems, VoIP gateways, conference servers and other custom solutions. It is used by small businesses, large businesses, call centers, carriers, and government agencies worldwide.

Asterisk is free and open source and is sponsored by Sangoma. Sangoma also offers commercial products that use Asterisk under the hood, and depending on your experience and budget, using these products may be more beneficial than rolling your own. Only you and your organization know that answer.

It should be noted that this guide requires the administrator to do a fair amount of research on their own. Installing a communications server is not a difficult process, but running one can be quite complicated. While this guide will get your server up and running, it will not be fully ready for you to use in production.

Prerequisites¶

At minimum, you will need the following skills and tools to complete this guide:

A machine running Rocky Linux
A comfort level with modifying configuration files and issuing commands from the command-line
Knowledge of how to use a command line editor (We are using vi here, but feel free to substitute in your favorite editor.)
You will need root access, and ideally be signed in as the root user in your terminal
The EPEL repositories from Fedora
The ability to login as root or run root commands with sudo. All commands here assume a user that has sudo rights, however the configuration and build processes are run with sudo -s.
To grab the latest build of Asterisk, you will need to either use curl or wget. This guide uses wget, but feel free to substitute in the appropriate curl string if you want to use that.

Update Rocky Linux and Install `wget`¶


sudo dnf -y update

This will get your server up-to-date with all packages that have been released or updated since the last update or installation. Then run:


sudo dnf install wget

Set Hostname¶

Set your hostname to the domain you'll be using for Asterisk.


sudo hostnamectl set-hostname asterisk.example.com

Add Needed Repositories¶

First, install the EPEL (Extra Packages for Enterprise Linux):


sudo dnf -y install epel-release

Next, enable Rocky Linux' PowerTools:


sudo dnf config-manager --set-enabled powertools

Install Development Tools¶


sudo dnf group -y install "Development Tools"
sudo dnf -y install git wget

Install Asterisk¶

Downloading and Configuring the Asterisk Build¶

Before you download this script, make sure you have the latest version. To do so, navigate to the Asterisk download link here and look for the latest build of Asterisk. Then copy the link location. As of the writing of this document, the following was the latest build:


wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-20-current.tar.gz 
tar xvfz asterisk-20-current.tar.gz
cd asterisk-20.0.0/

Before running the install_prereq below (and the remaining commands), you are going to need to be the superuser or root. It's much easier at this point to get into sudo permanently for a while. We will exit back out of sudo later in the process:


sudo -s
contrib/scripts/install_prereq install

You should see the following when the script completes:


#############################################
## install completed successfully
#############################################

Now that all of the required packages are installed, our next step is to configure and build Asterisk:


./configure --libdir=/usr/lib64 --with-jansson-bundled=yes

Assuming that the configuration runs without issue, you should get a large ASCII Asterisk emblem, followed by the following on Rocky Linux:


configure: Package configured for:
configure: OS type  : linux-gnu
configure: Host CPU : x86_64
configure: build-cpu:vendor:os: x86_64 : pc : linux-gnu :
configure: host-cpu:vendor:os: x86_64 : pc : linux-gnu :

This is one of the steps where the administrator is going to need to do his homework. There are a lot of menu options that you may or may not need. Running the following command:


make menuselect

will bring you to a menu select screen:

menuselect screen

Look through these options carefully and make selections based on your requirements. As stated earlier, this may take some additional homework.

Build and Install Asterisk¶

To build, we want to execute the following commands in succession:


make
make install

Installing the documentation isn't required, but unless you are a communications server expert, you'll want them installed:


make progdocs

Next install the basic PBX and make the config. The basic PBX is just that, very basic! You will probably need to make changes going forward to get your PBX to function as you want it to.


make basic-pbx
make config

Asterisk Configuration¶

Create User & Group¶

You'll need a specific user just for asterisk. Might as well create it now.


groupadd asterisk
useradd -r -d /var/lib/asterisk -g asterisk asterisk
chown -R asterisk.asterisk /etc/asterisk /var/{lib,log,spool}/asterisk /usr/lib64/asterisk
restorecon -vr {/etc/asterisk,/var/lib/asterisk,/var/log/asterisk,/var/spool/asterisk}

Now that the bulk of our work is completed, go ahead and exit out of the sudo -s command. This will require that most of the remaining commands use sudo again:


exit

Set Default User & Group¶


sudo vi /etc/sysconfig/asterisk

Remove the comments on the two lines below and save:


AST_USER="asterisk"
AST_GROUP="asterisk"


sudo vi /etc/asterisk/asterisk.conf

Remove the comments on the two lines below and save:


runuser = asterisk ; The user to run as.
rungroup = asterisk ; The group to run as.

Configure Asterisk Service¶


sudo systemctl enable asterisk

Configure Firewall¶

This example uses firewalld for the firewall, which is the default in Rocky Linux. The goal here is to open SIP ports to the world and to open RTP (Realtime Transport Protocol) to the world on ports 10000-20000 as recommended by the Asterisk documentation.

Keep in mind that you will almost certainly need other firewall rules for other forward-facing services (HTTP/HTTPS) which you will probably want to limit to your own IP addresses. That is beyond the scope of this document:


sudo firewall-cmd --zone=public --add-service sip --permanent
sudo firewall-cmd --zone=public --add-port=10000-20000/udp --permanent

Since we've made the firewalld commands permanent, we will need to do a reboot of the server. You can do that with:


sudo shutdown -r now

Test¶

The Asterisk Console¶

To test, let's connect to the Asterisk console:


sudo asterisk -r

Which will bring you into the Asterisk command-line client. You will see this prompt after the basic Asterisk information is displayed:


asterisk*CLI>

To change the verbosity of the console, use the following:


core set verbose 4

Which should show you the following in the Asterisk console:


Console verbose was OFF and is now 4.

Show Sample End-Point Authentications¶

At the Asterisk command-line client prompt, type:


pjsip show auth 1101

This will return username and password information that you can then use to connect any SIP client with.

Conclusion¶

The above will get you up and running with the server, but finishing out the configuration, connecting devices, and further troubleshooting is up to you.

Running an Asterisk communications server takes a lot of time and effort and will require a lot of research by any administrator. For more information on how to configure and use Asterisk, take a look at the Asterisk Wiki here.

Contributors: Steven Spencer, Ganna Zhyrnova