Asterisk – IT Blog

Installing Asterisk on Ubuntu Server

I will give an example of a quick installation of Asterisk on Ubuntu Server.
I will install it on versions 14.04 LTS and 16.04 LTS.

Configuring GOIP4 with Asterisk

On the test, I set up a Chinese GSM GOIP4 gateway with an Asterisk server as a trunk.

Asterisk commands

I will describe the possible Asterisk commands that can be entered after connecting to the console:

Monitoring Asterisk in Zabbix

We will monitor Asterisk through Zabbix agent, for this we install it on the same machine as Asterisk.

Frequent messages “Remote UNIX connection” in Asterisk

I noticed once in the Asterisk console that the following messages are often displayed:

— Remote UNIX connection
— Remote UNIX connection disconnected
— Remote UNIX connection
— Remote UNIX connection disconnected
— Remote UNIX connection
— Remote UNIX connection disconnected
…

Notice “Call from X to extension X rejected because extension not found in context X”

Once I was asked by a client to see why he could not get through to one of the numbers.
I opened the asterisk console:

How to configure Asterisk AMI

Asterisk Managment Interface (AMI) – a powerful API interface for Asterisk, allows you to manage, execute commands, receive notifications about events in real time, etc.

IPTables rules for Asterisk AMI

Suppose the default “iptables -P INPUT ACCEPT” for all connections (and if DROP, which is very desirable, then we do not use all the DROP rules below, we only perform ACCEPT).

Since Asterisk AMI usually works on TCP port 5038, in order to open it we will execute:

Increase the volume of calls in Asterisk

To increase the call volume during calls, you need to add a couple of lines (on which you need to increase the volume) in the /etc/asterisk/extensions.conf file, at the beginning of each dialplan:

Installation of the echo canceller Oslec and DAHDI

Once I installed a Chinese TDM410P card for connecting analog telephone lines and a bundle of Asterisk + Dahdi.
Since the board has no hardware noise cancellation, Oslec had to be installed.
When making calls, there was no echo from the side of the analog telephone, but whoever spoke into the IP phone heard himself.