FreeSWITCH Beginner’s Notes

There are little things one may forget while learning FreeSWITCH. This page aims to make a list of such things.

Modify RTP Port Range

To edit RTP ports or port range, you need to edit the freeswitch/conf/autoload_configs/switch.conf.xml file. The following are the parameters you need to modify:

<param name="rtp-start-port" value="10000"/>
<param name="rtp-end-port" value="50000"/>

My experience has been that you need to restart FreeSWITCH to make this change effective. Simply doing reloadxml did not work for me.

Modify SDP

If you want to edit, modify, or mangle SDP, use switch_r_sdp. For more information visit Codec Negotiation.

Sample Outbound Dial Plan

Let’s say you want to create a dial plan for a particular number, say 1235551010, and want to change the From header to the format CallerID@FreeSwtichIP, then your dial plan may look something like this:

<context name="myoutplan">
<extension name="outbound_one_number">
<condition field="destination_number" expression="^(1235551010)$">
<action application="bridge" data="{sip_from_uri=sip:${caller_id_number}@}sofia/gateway/myoutboundgateway/$1" />