My Technical Handbook: FreeSWITCH Getting Started Guide

From FreeSWITCH Wiki

The purpose of the following page is to instruct new users on how to configure FreeSWITCH™ in a basic way. It is also intended to provide people with a basic understanding of the configuration files and how they are processed. If FreeSWITCH™ is not already installed on your system you should read the Installation Guide. This guide is not intended to allow for more than a default configuration.

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3 Configuring FreeSWITCH

3.3 dialplan

3.3.1 Some common extensions for testing

3.4 directory

4 Running FreeSWITCH

6.3.1 Example freeswitch.xml

FreeSWITCH layout

FreeSWITCH™ has a modular design. This design allows it to be extended without breaking functionality or requiring massive recoding efforts. Each module provides specific functionality, often commands that are related are grouped into one module. You will need to enable the modules that you desire, based on their function. By default FreeSWITCH™ comes with a good set of modules loaded, to enable most basic functionality.
Read up on the default config for more information.

Configuration

The following sections will show you each step that you will have to take to get a functional system.

Firewall

If you are going to route traffic across your network, you need to ensure that you do not have a firewall blocking traffic on the specified network paths. Commonly firewalls are installed at egress points, where your local network connects to the internet. This is not always the case in some corporate environments. If you are not responsible for your network, you may wish to contact the group or individuals who are responsible for it.
Information they may need to enable traffic would include the port numbers. Various protocols use different ports for different things. Some you need bi-directional connectivity, some you only need outbound. Depending on your call scenario you may only need to allow connections that are initiated by your system. If you have any problems with protocols not working, it is recommended that you disable your firewall to the FreeSWITCH™ system, place a test call, and see if the problem persists. A misconfigured firewall is responsible for many common problems.
For more information, including the ports which need to be configured, see the Firewall page.

Configuration Files

FreeSWITCH™ configuration data is stored in XML format. These files are located in the conf directory under the FreeSWITCH™ install directory. By default on a Unix-like system this will be /usr/local/freeswitch/conf. There are preprocessor markup tags that tell the configuration parser to perform tasks, such as including other files, which are carried out before the XML is parsed.

Folder	Description
autoload_configs	These configuration files are loaded automatically into FreeSWITCH. They contain configuration information for almost all core modules.
dialplan	This is the place where you setup your dialplan. There are some examples of how to configure your dialplan included.
directory	The directory contains all users that may register and use freeswitch as their PBX.
jingle_profiles	Jingle is the mod that FS uses to handle XMPP. Profiles tells FS how to use the protocol. Each profile has its own ip port.
lang	Tells FS how to say currency etc in different languages
mrcp_profiles	MRCP is used to allow FreeSWITCH to use speech recognition and TTS
sip_profiles	Tells FS how to talk sip. Each profile has it's own port.

Configuring FreeSWITCH

This guide aims to explain the default configuration layout and how you configure it to your liking. Read up on the default config for more information.

This layout is in no way required, you can minimize the configuration to just one file if needed. The main config file is called freeswitch.xml, you don't need to change it in any way, it just loads all other config files.

vars.xml

vars.xml is used to define a couple of variables that are used system wide. NOTICE you can not comment these X-PRE-PROCESS lines out. They will still be active in an XML comment.
See Config_vars.xml for example.
In the default configuration the vars.xml file is used to define some preprocessor variables. In a first time setup you will most likely want to set:
<X-PRE-PROCESS cmd="set" data="outbound_caller_name=FreeSWITCH"/>
<X-PRE-PROCESS cmd="set" data="outbound_caller_id=8777423583"/>
<X-PRE-PROCESS cmd="set" data="call_debug=false"/>directives for use in other portions of the configuration.
The default port of Freeswitch is also defined in
<param name="sip-port" value="5060" />

autoload_configs

autoload_configs is a directory where a lot of the freeswitch configuration resides. This directory is located in $PREFIX/conf/autoload_configs. The default freeswitch.xml preprocesses xml files matched by the glob conf/autoload_configs/*.xml

modules.conf.xml

See modules.conf.xml for an example of modules.conf.xml.
modules.conf.xml tells freeswitch which modules to load. There are certain modules required for operation so you should not edit this file unless you know that you wish to add or remove a specific module

sofia.conf.xml

mod_sofia is used to create SIP endpoints in FreeSWITCH. If you are familiar with Asterisk, each SIP Profile in mod_sofia is similar to chan_sip in Asterisk, though much more powerful.
The sofia.conf.xml file contains a "X-PRE-PROCESS" directive that includes other XML files (within, by default, conf/sip_profiles/) that define one or more "SIP Profiles". A SIP Profile is a SIP UA (User Agent or an endpoint), which communicates with other SIP endpoints.
A "User Agent" ("UA") is an application used for running a certain network protocol. A Sofia User Agent is the same thing but the protocol in that case is SIP. In FreeSWITCH terms, User Agent = UA = Sofia Profile = SIP Profile.
See Sofia_Configuration_Files for an example sofia.conf.xml.
See also SIP Network Elements on wikipedia.

What SIP Profiles Do

The SIP Profiles in FreeSWITCH can often lead to confusion. Unlike other softswitches (like Asterisk), FreeSWITCH allows you to handle media (calls, video, etc.) differently based on where the equipment is attached to your network. This assists with security as well as providing added functionality.
SIP Profiles allow you to define paths to devices or carriers that may live inside or outside your network. These paths can be of many different types, but must consist of a unique combination of port and IP pairs. You could have SIP profiles for your internal network, or multiple profiles for each subnet of your internal network, or even completely different protocols like IPv6 as profile definitions. This helps FreeSWITCH identify how to route different types of calls when necessary, and also gives you the flexibility to tailor your dialplans based on what path a call originates to/from.
In the sample configuration there are three default categories for where a SIP Profile can reside. Each profile is detailed below.

SIP_Profiles

The default profiles are "internal" and "external", each serves a special purpose so it would be wise to understand what they do.

Internal

File Location: $PREFIX/conf/sip_profiles/internal.xml
This profile generally refers to devices that reside on your internal network. Those devices will inherit all configuration options in the internal profile you setup. This is typically your internal phones with extensions. By default, these devices must use SIP authentication.
The Internal (formerly called "default") SIP profile is configured to listen on the primary IP address of the machine (unless you set $${domain} to something else in vars.xml) on port 5060 (the default SIP port). The internal SIP profile does authenticate calls and is not suitable for configuring trunks to providers or outside phones, in most cases (i.e., use the External profile for configuring trunks to providers or outside phones).
The Internal profile should be used if you intend on handling registration for sip clients (ie a SIP registrar). You may wish to skip to the section Getting_Started_Guide#directory to configure additional sip clients.
Authenticated users of this profile are normally set (via the variable user_context) to use the dialplan defined in the default context.
See Config_default.xml

External

File Location: $PREFIX/conf/sip_profiles/external.xml
This profile generally refers to devices or gateways that reside outside of your network. Generally this is where you define your external trunks/VoIP carriers/etc. Again, those devices will inherit all configuration options in the external profile you setup.
The External (formerly "outbound") profile handles outbound registrations to a SIP provider. The SIP provider sends calls to you, and you send calls to your provider, through the external profile. The external profile allows anonymous calling, which is required as your provider will never authenticate with you to send you a call.
In order to secure your FreeSWITCH it is wise to link your outbound profile to a dialplan context other than 'default', which in the default configuration is the where authenticated users are placed.
NOTE: The default port for external connections is 5080. This also means if you are trying to connect a phone remotely to your FreeSWITCH box, you must set it to connect on port 5080, or change your ports around. This confuses a lot of people. As an example, in X-Lite, if you are connecting to FS from the outside, set your server as "my.server.com:5080".
The dialplan for this profile (per-default) is defined in the public context
See Config_external.xml

NAT

The nat.xml file (and profile) have been deprecated. Use the External Profile and port 5080.

Other Profile Concepts

Ideas for other SIP profiles you might end up building:

Routing IPv6
Having multiple profiles for different networks or subnets
Having multiple profiles for different remote hosts/endpoints (remote offices, etc.)

dialplan

The FreeSWITCH dialplan is a full-featured, XML-based call-routing mechanism. (There also exists support for Asterisk-like dialplans as well as really fancy real-time and/or back-end database-driven dialplans.) The best place to get started in learning about the FreeSWITCH dialplan is the Dialplan page here on the wiki. It discusses the basics of the FreeSWITCH dialplan. If you need an XML primer check out the information on the Basic_XML page which will get you pointed in the right direction. There are two other important resources for you to learn more about the diaplan: the small-but-growing Dialplan_Recipes page as well as the default dialplan that comes with a standard FreeSWITCH installation.
It is recommended that you compile FreeSWITCH with the default configuration and make sure it works before you start making customizations. Note that the default config files, including the default.xml dialplan, are still being updated. It makes sense to put your custom diaplan entries into the extensions subdirectory under conf/dialplan. You may create one or more XML files in this subdirectory, all of which will be included in the dialplan thanks to an "include" directive in the default.xml file. By keeping your customized extensions separate from default.xml you will be able to update default.xml without having to re-enter your custom extensions.

Some common extensions for testing

1000, 1001, ..., 1019 - Generic SIP extensions
5000 - demo IVR (requires sounds and music files to be installed)
9995 - five second delay echo test
9996 - standard echo test
9999 - music on hold (requires music files to be installed)

Running FreeSWITCH

Starting FreeSWITCH™ is done from the command-line. The location of the executable varies depending on your system.

Starting in Unix-based Systems

Now that you have compiled and configured FreeSWITCH™ its time to place a test call to ensure that everything is working so far. To start FreeSWITCH™ change to the bin subdirectory under the FreeSWITCH™ installation directory, and run FreeSWITCH™. In a unix-like system that might be:

cd /usr/local/freeswitch/bin
./freeswitch

REDHAT CENTOS Startup Scripts:
cp build/freeswitch.init.redhat /etc/init.d/freeswitch
chmod 755 /etc/init.d/freeswitch

Starting in Windows-based Systems

The Visual Studio project runs via an executable located under the debug or release folder of your project's directory tree (depending on how your project was built). On a debug build of the Windows system start FreeSWITCH™ as follows:

cd <PROJECT FOLDER>\debug
FreeSwitch.exe

The FreeSWITCH™ command line will be available after successful loading of the application.

Command Line Parameters

These are the optional arguments you can pass to freeswitch:
-conf [confdir] -- specify an alternate config dir
-db [dbdir] -- specify an alternate db dir
-help -- this message
-hp -- enable high priority settings
-log [logdir] -- specify an alternate log dir
-nc -- do not output to a console and background
-nf -- no forking
-nonat -- do not load NAT (network address translation, for firewalls)
-stop -- stop freeswitch
-waste -- don't consume tons of unix resources (file handles)

Shutting Down FreeSWITCH™

To exit the FreeSwitch CLI, simply type 'shutdown' or '...'. Note, this will shutdown FreeSwitch. If you do not wish to shutdown FreeSwitch, it is suggested to start the process inside of a "screen" session; In Windows, FreeSWITCH™ may be started as a service. It is not recommended that you start FreeSWITCH™ as a service until you are certain your configuration is valid. Also if started from a remote login session (IE SSH) it is not advised to terminate the connection with FS left in the foreground.

Some stuff to try out!

The optimal way of testing is to get a pair of SIP phones and try out features via the default dialplan. If you're already familiar with asterisk, you could also start out by Connecting Freeswitch And Asterisk

Let's assume for the example that you have your SIP phones registered as extensions 1000 and 1001.
You can use extension numbers 1000 through 1019 with a password of 1234 (the default voice-mail password is the same number as the extension {Ex: Extension 1000 has its voice-mail password set to 1000}.

A sample configuration with X-Lite is shown below:

Once you've done that, you can try out a bunch of features already setup in the test dialplan.

Basic Calling

Call between 1000 and 1001 by dialing the respective extension.
Call 4000 to login to your voicemail box.
870 - Redial last called # from this extension.
*69 - Call back the last person to call this extension.
8+[ext] - Place an intercom call to extension [ext]. If no answer, it does not go to voicemail but just keeps ringing. Some phones have additional functionality for intercom calls.

Advanced Calling Features

88+[ext] - Eavesdrop on extension [ext] (ex: 881001). That extension must be on an active call. Once connected, you can listen to the call without being heard, or you can...

Press 1 to barge in with the distant party.
Press 2 to barge in with the local party.
Press 3 to barge in on both parties.

5900 - Park a call in a hold queue (First-in-first-out style).
5901 - Pickup a call parked in queue (that was put there via 5900).

Group Assignments The below functions involve the idea of keeping a database/table of which extensions belong to one of 100 groups (numbered 00-99).

80+[group] - Delete this extension from calling group #[group] (can be two digits 00-99). A beep tone confirms the function worked.
81+[group] - Add this extension to calling group #[group] (can be two digits 00-99). A beep tone confirms the function worked.
82+[group] - Simultaneously ring all extensions in group #[group]. The first person to answer will be connected to you automatically.

Conferencing

30+[conf] - Join conference #[conf] - 8kHz quality.
31+[conf] - Join conference #[conf] - 16kHz quality.
32+[conf] - Join conference #[conf] - 32kHz quality.
9888 - Join the FreeSWITCH conference via a SIP Internet connection (8kHz).
91616 - Join the FreeSWITCH conference via a SIP Internet connection (16kHz).

Note: Conference rooms are unique for the bit-level you choose (i.e. 3000 for conference room 00 will not join with participants in 3100 which is also conference room 00. They are different conferences).

Interactive Voice Response

5000 - IVR demo.

Other Tests

9992 - Info test (prints information to the command line interface).
9995 - Echo test (5-second delay before returning echo).
9996 - Echo test (real-time).
9997 - Play milliwatt tone.
9998 - Tetris, via tone streaming.
9999 - Test Music On Hold out (if you installed sound files).

Advanced

Preprocessor Commands

The FreeSWITCH™ configuration supports preprocessor commands reminiscent of (but not matching) apache server-side includes: #comment, #include and #set.
In addition to the pre-processor PIs, which may appear anywhere, the freeswitch.xml file has a root element of "document", and all its children are "section" elements, with "name" attribute values being one of:

Note that preprocessor variables set with a #set PI are unrelated to "channel variables", defined with the <variable> element. Those variables are only expanded within channels.
Preprocessor commands are included in XML style comment brackets. Even though they appear commented to an XML parser, they are still processed. The comment characters are required or they will not be processed. An example would be:

freeswitch.xml

This is the main configuration file, and the only one that has a fixed name. When you start FreeSWITCH™ it will locate this file and process it. The default freeswitch.xml file includes other files to allow for easier maintenance of configuration data. The default configuration of most of these files is suitable for first time users, until you become more familiar with FreeSWITCH™ it is advised that you leave them to their default settings.
freeswitch.xml is divided into multiple sections, and each section is used by a different component in FreeSWITCH™. The sections are as follows:

The "configuration" section has children for switch.conf and modules.conf which are used by the core, as well as a child for each module in use.
The dialplan section defines which action to invoke when a call arrvies to the switch.
The directory defines the users that can connect to the switch (user agents).
The phrases section defines where freeswitch can find the sound files, and if it can use any TTS engines.

The structure below "document" and "section" varies according to the parent. There is currently no dtd/relaxng/xmlschema available to validate the file, though since it does not use xml mechanisms for inclusion that would be an obstacle to true validation (and the limited xml parser used by FreeSwitch doesn't implement any of the XML standard mechanisms such as external entities or XInclude). XML namespaces are not currently used. There is no application-level versioning within the file.

How the configuration files are parsed

FS begins with its single, master configuration file (conf/freeswitch.xml). This master config file then loads (via "globs" e.g. "*.xml") additional config files. FS 1.0.4 installs with dozens of config files. You may stray daringly far from the stock install and arrange the files (and the loading thereof) however you wish: it's up to you if you want a single, huge config file or a series of config files. Each config file can include none or many other config files. Whatever method you choose, at runtime FreeSwitch parses all the (one or many) files into a single, huge, resultant "running config" file (located at log/freeswitch.xml.fsxml) which mustn't be edited while FS is running as portions are memory-mapped into FS.
IMPORTANT When the FS console reports a configuration error, the line number it gives is the line number in the "running config" file, not the line number in any included file.

Example freeswitch.xml

Below is a snippet freeswitch.xml file. Of course, the bulk of the configuration is found in the included files.

<?xml version="1.0"?>
<document type="freeswitch/xml">
<X-PRE-PROCESS cmd="include" data="vars.xml"/>

<section name="configuration" description="Various Configuration">
<X-PRE-PROCESS cmd="include" data="autoload_configs/*.xml"/>
</section>

<section name="dialplan" description="Regex/XML Dialplan">
<X-PRE-PROCESS cmd="include" data="dialplan/*.xml"/>
</section>



<section name="directory" description="User Directory">
<X-PRE-PROCESS cmd="include" data="directory/*.xml"/>
</section>


<section name="phrases" description="Speech Phrase Management">
<macros>
<X-PRE-PROCESS cmd="include" data="lang/*/*.xml"/>
</macros>
</section>
</document>

Preprocessor Variables

For now, do not worry about all of the configuration properties, this guide will show you the minimum required to get a running FreeSWITCH™ system. After you have verified your installation you may then configure the system in more detail.
The first thing you should do is review conf/vars.xml and conf/freeswitch.xml. For now just make note of the preprocessor variables.

<X-PRE-PROCESS cmd="set" data="bind_server_ip=auto"/>
<X-PRE-PROCESS cmd="set" data="global_codec_prefs=G722,PCMU@20i,PCMA@20i"/>

"bind_server_ip" Can be an ip address, a dns name, or "auto".
"global_codec_prefs" has a default of G.711 u-law. You can probably leave this alone, unless you need to change it to another codec, but most VoIP equipment will support this codec.

hint: If you need to troubleshoot your configuration, the log/freeswitch.xml.fsxml file contains the entire pre-processed freeswitch.xml file. (For testing and troubleshooting you could replace the freeswitch.xml file with this copy.)
hint2: If you have a [multihomed NIC] (Single Link, Multiple IP address) then remember that you may have to set a pre-process variable in the vars.xml file.
<X-PRE-PROCESS cmd="set" data="local_ip_v4=<your ip address>"/>

Multi-Tenant Info / Multiple Company HOWTO

The Multi-tenant page gives details regarding running FS to support multiple separate companies. Multiple Companies is a HOWTO that describes setting up two independent companies on FS, where the files go, what they must contain, etc.

2 comments:

anaaya foodsJuly 16, 2019 at 1:46 AM
Nice post...
I want to share with FreeSwitch GuI applications.
You can found number system where you can get FreeSWITCH GUIs.
Deniz GezmisDecember 19, 2022 at 9:54 PM
Great write-up. Just a quick question.. Rather than using (default) 4-digit extensions, how/where can we setup 2-digit extensions? Thanks,.

My Technical Handbook

FreeSWITCH Getting Started Guide