freeswitch/conf/minimal/autoload_configs/switch.conf.xml

<configuration name="switch.conf" description="Core Configuration">
  <settings>
    <param name="colorize-console" value="true"/>

    <!-- Max number of sessions to allow at any given time -->
    <param name="max-sessions" value="1000"/>
    <!--Most channels to create per second -->
    <param name="sessions-per-second" value="30"/>

    <!-- Default Global Log Level - value is one of debug,info,notice,warning,err,crit,alert -->
    <param name="loglevel" value="debug"/>

    <!-- RTP port range -->
    <param name="rtp-start-port" value="16384"/>
    <param name="rtp-end-port" value="32768"/>
  </settings>
</configuration>