Asterisk is a free and open source framework created by Sangoma for building communications applications both for small companies and for large scale use cases. Asterisk is a software based solution which turns your Old computer into a communications server that powers IP PBX systems, VoIP gateways, conference servers and other custom solutions. The solutions build by Asterisk powers call centers, carriers and government agencies worldwide.

In this blog post we’ll walk though the installation of Asterisk 17 on Ubuntu 20.04|18.04 server. As of this writing the latest release of Asterisk is 17. Also note this is not a long term release and should not be used for production deployments that need Digium support for long years.

Some key points about Asterisk are:

  • It is written in the C Programming Language
  • It is written to run on Linux and other types of Unix
  • It powers Business Telephone Systems
  • It connects many different Telephony protocols
  • It is a toolkit for building IP PBX with many powerful features and applications , VoIP Gateways and Conferencing systems
  • Has support for VoIP Phones as well as PSTN and POTS  
  • It uses SIP , the most common VoIP protocol, among others

You’ll follow the steps in the next sections to install Asterisk 17 on Ubuntu 20.04|18.04 Linux system. Since Asterisk is created to be modular, adding extra features after installation is not a difficult process. It can be easily done.

Step 1: Update Ubuntu System

We’ll start our installation by updating our APT package index and upgrading all packages installed on the system. I recommend you perform this installation in a new system to avoid any issues with running services.

sudo apt update
sudo apt -y upgrade

If the upgrade process was successful you can then reboot your system.

sudo systemctl reboot

Step 2: Install Build Dependencies

After system is rebooted login and install all dependencies required to build Asterisk on Ubuntu 20.04|18.04 Linux machine.

sudo apt update
sudo add-apt-repository universe
sudo apt -y install git curl wget libnewt-dev libssl-dev libncurses5-dev subversion  libsqlite3-dev build-essential libjansson-dev libxml2-dev  uuid-dev

The installation should only take few minutes if you have a decent internet connection.

Step 3: Download Asterisk 17 tarball

You won’t find the latest release of Asterisk in the official system repositories. We’ll have to manually download the tarball and build the application from source.

On Ubuntu 20.04, the version available in APT repositories is 16.

$ sudo apt policy asterisk
asterisk:
  Installed: (none)
  Candidate: 1:16.2.1~dfsg-2ubuntu1
  Version table:
     1:16.2.1~dfsg-2ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu focal/universe amd64 Packages
        500 http://mirror.hetzner.de/ubuntu/packages focal/universe amd64 Packages

Use wget command to download archive file.

cd ~
wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-17-current.tar.gz

Extract the file with tar.

tar xvf asterisk-17-current.tar.gz

Run the following command to download the mp3 decoder library into the source tree.

cd asterisk-17*/
contrib/scripts/get_mp3_source.sh

Expected command execution output:

A    addons/mp3
A    addons/mp3/MPGLIB_README
A    addons/mp3/common.c
A    addons/mp3/huffman.h
A    addons/mp3/tabinit.c
A    addons/mp3/Makefile
A    addons/mp3/README
A    addons/mp3/decode_i386.c
A    addons/mp3/dct64_i386.c
A    addons/mp3/MPGLIB_TODO
A    addons/mp3/mpg123.h
A    addons/mp3/layer3.c
A    addons/mp3/mpglib.h
A    addons/mp3/decode_ntom.c
A    addons/mp3/interface.c
Exported revision 202.

Ensure all dependencies are resolved:

sudo contrib/scripts/install_prereq install

You should get a success message at the end:

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

Step 4: Build and Install Asterisk 17 on Ubuntu 20.04|18.04

After installation of dependencies you should be ready to build Asterisk 17 from the source we downloaded.

Run the configure script to satisfy build dependencies.

./configure

A success should have an output like below:

.....
configure: creating ./config.status
config.status: creating makeopts
config.status: creating autoconfig.h
configure: Menuselect build configuration successfully completed

               .$$$$$$$$$$$$$$$=..
            .$7$7..          .7$$7:.
          .$$:.                 ,$7.7
        .$7.     7$$$$           .$$77
     ..$$.       $$$$$            .$$$7
    ..7$   .?.   $$$$$   .?.       7$$$.
   $.$.   .$$$7. $$$$7 .7$$$.      .$$$.
 .777.   .$$$$$$77$$$77$$$$$7.      $$$,
 $$$~      .7$$$$$$$$$$$$$7.       .$$$.
.$$7          .7$$$$$$$7:          ?$$$.
$$$          ?7$$$$$$$$$$I        .$$$7
$$$       .7$$$$$$$$$$$$$$$$      :$$$.
$$$       $$$$$$7$$$$$$$$$$$$    .$$$.
$$$        $$$   7$$$7  .$$$    .$$$.
$$$$             $$$$7         .$$$.
7$$$7            7$$$$        7$$$
 $$$$$                        $$$
  $$$$7.                       $$  (TM)
   $$$$$$$.           .7$$$$$$  $$
     $$$$$$$$$$$$7$$$$$$$$$.$$$$$$
       $$$$$$$$$$$$$$$$.

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 :

Setup menu options by running the following command:

make menuselect

Use arrow keys to navigate, and Enter key to select.

Select Addons to enable.

<img alt="" data-ezsrc="https://kirelos.com/wp-content/uploads/2020/08/echo/install-asterisk-ubuntu-18.04-01-min.png" ezimgfmt="rs rscb8 src ng ngcb8" src="data:image/svg xml,”>

Enable Core sound modules you want to use.

<img alt="" data-ezsrc="https://kirelos.com/wp-content/uploads/2020/08/echo/install-asterisk-ubuntu-18.04-02-min.png" ezimgfmt="rs rscb8 src ng ngcb8" src="data:image/svg xml,”>

You can also add additional MOH packages you want to use.

<img alt="" data-ezsrc="https://kirelos.com/wp-content/uploads/2020/08/echo/install-asterisk-ubuntu-18.04-03-min.png" ezimgfmt="rs rscb8 src ng ngcb8" src="data:image/svg xml,”>

Do the same for Extra Sound Packages.

<img alt="" data-ezsrc="https://kirelos.com/wp-content/uploads/2020/08/echo/install-asterisk-ubuntu-18.04-04-min.png" ezimgfmt="rs rscb8 src ng ngcb8" src="data:image/svg xml,”>

You can also go through the other menus and select options you see fit for your use case.

When done run the following command to build Asterisk 17 on Ubuntu 20.04|18.04.

make

Here is my successful build output:

.....
TROLEnc.o ooh323cDriver.o -> chan_ooh323.so
   [CC] format_mp3.c -> format_mp3.o
   [CC] mp3/common.c -> mp3/common.o
   [CC] mp3/dct64_i386.c -> mp3/dct64_i386.o
   [CC] mp3/decode_ntom.c -> mp3/decode_ntom.o
   [CC] mp3/layer3.c -> mp3/layer3.o
   [CC] mp3/tabinit.c -> mp3/tabinit.o
   [CC] mp3/interface.c -> mp3/interface.o
   [LD] format_mp3.o mp3/common.o mp3/dct64_i386.o mp3/decode_ntom.o mp3/layer3.o mp3/tabinit.o mp3/interface.o -> format_mp3.so
   [CC] res_config_mysql.c -> res_config_mysql.o
   [LD] res_config_mysql.o -> res_config_mysql.so
Building Documentation For: third-party channels pbx apps codecs formats cdr cel bridges funcs tests main res addons
  --------- Asterisk Build Complete --------- 
   Asterisk has successfully been built, and  
   can be installed by running:               
                                              
                  make install                
  ------------------------------------------- 

This is the command you’ll run to install Asterisk 17 on Ubuntu 20.04:

sudo make install

Sample output:

....
make[1]: Entering directory '/home/jkmutai/asterisk-17.6.0/sounds'
make[1]: Leaving directory '/home/jkmutai/asterisk-17.6.0/sounds'
find rest-api -name "*.json" | while read x; do 
	/usr/bin/install -c -m 644 $x "https://computingforgeeks.com/var/lib/asterisk/rest-api" ; 
done
  ---- Asterisk Installation Complete ------- 
                                              
      YOU MUST READ THE SECURITY DOCUMENT     
                                              
   Asterisk has successfully been installed.  
   If you would like to install the sample    
   configuration files (overwriting any       
   existing config files), run:               
                                              
   For generic reference documentation:       
      make samples                            
                                              
   For a sample basic PBX:                    
      make basic-pbx                          
                                              
                                              
  -----------------  or --------------------- 
                                              
   You can go ahead and install the asterisk  
   program documentation now or later run:    
                                              
                 make progdocs                
                                              
   **Note** This requires that you have       
   doxygen installed on your local system     
  ------------------------------------------- 

You can optionally install documentation:

sudo make progdocs

Finally, install configs and samples.

sudo make samples
sudo make config
sudo ldconfig

Step 5: Start Asterisk Service on Ubuntu 20.04|18.04

Create a separate user and group to run asterisk services, and assign correct permissions:

sudo groupadd asterisk
sudo useradd -r -d /var/lib/asterisk -g asterisk asterisk
sudo usermod -aG audio,dialout asterisk
sudo chown -R asterisk.asterisk /etc/asterisk
sudo chown -R asterisk.asterisk /var/{lib,log,spool}/asterisk
sudo chown -R asterisk.asterisk /usr/lib/asterisk

Set Asterisk default user to asterisk:

$ sudo vim /etc/default/asterisk
AST_USER="asterisk"
AST_GROUP="asterisk"

$ sudo vim /etc/asterisk/asterisk.conf
runuser = asterisk ; The user to run as.
rungroup = asterisk ; The group to run as.

Restart asterisk service after making the changes:

sudo systemctl restart asterisk

Enable asterisk service to start on system  boot:

sudo systemctl enable asterisk

Check service status to see if it is running.

$ systemctl status asterisk
● asterisk.service - LSB: Asterisk PBX
     Loaded: loaded (/etc/init.d/asterisk; generated)
     Active: active (running) since Fri 2020-08-14 12:04:41 CEST; 9s ago
       Docs: man:systemd-sysv-generator(8)
      Tasks: 82 (limit: 4567)
     Memory: 44.6M
     CGroup: /system.slice/asterisk.service
             └─54142 /usr/sbin/asterisk -U asterisk -G asterisk

Verify you can connect to Asterisk Command Line interface.

$ sudo asterisk -rvv
Asterisk 17.6.0, Copyright (C) 1999 - 2018, Digium, Inc. and others.
Created by Mark Spencer <[email protected]>
Asterisk comes with ABSOLUTELY NO WARRANTY; type 'core show warranty' for details.
This is free software, with components licensed under the GNU General Public
License version 2 and other licenses; you are welcome to redistribute it under
certain conditions. Type 'core show license' for details.
=========================================================================
Running as user 'asterisk'
Running under group 'asterisk'
Connected to Asterisk 17.6.0 currently running on ubuntu (pid = 54142)
ubuntu*CLI>

If you have an active ufw firewall, open http ports and ports 5060,5061:

sudo ufw allow proto tcp from any to any port 5060,5061

You now have Asterisk 17 installed and working on Ubuntu 20.04|18.04 Linux server.

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