fusionpbx/app/dialplans/resources/switch/conf/dialplan/505_call-forward-all.xml

<context name="${domain_name}">
  <extension name="call-forward-all" number="" app_uuid="57cf8f1f-9a2e-4996-bd80-d9300249b1ca" global="true" order="505">
    <condition field="${user_exists}" expression="true"/>
    <condition field="${forward_all_enabled}" expression="true">
      <action application="export" data="sip_h_Diversion=&lt;sip:${caller_destination}@${external_sip_ip}:5060&gt;;reason=unconditional"/>
      <action application="transfer" data="${forward_all_destination} XML ${domain_name}"/>
    </condition>
  </extension>
</context>