How to auto-provision IP phones with DHCP 'option 66'

After you have created the extension in 3CX PhoneSystem, entered the MAC address of the phone, and specified the model, you will need to configure the phone to retrieve the configuration from the 3CX PhoneSystem provisioning URL. When deploying a large number of IP phones on your network, it is best to use DHCP 'option 66' to automatically instruct the phone with the provisioning URL. For the purposes of this FAQ, we will assume that the DHCP Server to be configured is running Microsoft’s DHCP server, and that the IP Address of the 3CX PhoneSystem machine is 10.172.0.2.

  1. Open your DHCP Console.
  2. Expand the Reservations node of your DHCP Scope.
  3. Right Click the “Reservations” node and select “New Reservation”.
  4. Enter a friendly name for the phone you are creating a reservation for.
  5. Enter the IP Address that you wish to be assigned to the phone.
  6. Enter the MAC address of the phone, using lower case letters and no spaces or other characters.
  7. Click “Add”.
  8. Your new reservation will now appear in the reservation list. Right click on the reservation and click “Configure Options”.
  9. Scroll down the list and enable Option 66.
  10. Each phone vendor will require the Option 66 string to be in a particular format, and the format also changes depending whether the 3CX PhoneSystem was installed for Cassini or for IIS. Please review this list to identify the correct string for your phones:

    3CX PhoneSystem for Cassini

    Aastra Phones
    http://10.172.0.2:5481/provisioning/

    Grandstream Phones
    10.172.0.2:5481/provisioning

    Polycom Phones
    http://10.172.0.2:5481/provisioning/

    Snom Phones
    http://10.172.0.2:5481/provisioning/cfg{mac}

    Cisco SPA5XXG Phones
    http://10.172.0.2:5481/provisioning/$MA.xml

    Yealink T2x Phones
    http://10.172.0.2:5481/provisioning/
     
    3CX PhoneSystem for Microsoft IIS

     Aastra Phones
    http://10.172.0.2/management/provisioning/

    Grandstream Phones
    10.172.0.2/management/provisioning

    Polycom Phones
    http://10.172.0.2/management/provisioning/

    Snom Phones
    http://10.172.0.2/management/provisioning/cfg{mac}

    Cisco SPA5XXG Phones
    http://10.172.0.2/management/provisioning/$MA.xml

    Yealink T2x Phones
    http://10.172.0.2/management/provisioning/

  11. Once you apply the changes, the completed DHCP entry will look similar to the following:
     
  12. Switch on the phone. Once the telephone set is booted up, the phone set’s IP address will be displayed on the screen, and the phone should have successfully registered with 3CX PhoneSystem.

Notes:

  1. This document assumes that the phone is new or has been reset to "Factory Defaults". If in doubt, reset to "Factory Defaults.
  2. Linksys phones cannot use Option 66 for HTTP URLs. To provision a Linksys Phone (assuming the phone has IP Address 10.172.0.150), simply launch a browser on the same LAN as the Linksys Phone AND the PBX, and run the following URL (note difference between Cassini and IIS scenarios:

    3CX PhoneSystem for Cassini:
    http://10.172.0.150/admin/resync?http://10.172.0.2:5481/provisioning/spa$PSN.cfg

    3CX PhoneSystem for Microsoft IIS:
    http://10.172.0.150/admin/resync?http://10.172.0.2/management/provisioning/spa$PSN.cfg

  3. If you need a solution that does not require DHCP Option 66, you can also manually insert the provisioning URL in each phone, according to the phone specific configuration guides.

SIP Phone Configuration Guides (Preferred)

SIP Phone Configuration Guides (Supported)

SIP Phone Configuration Guides (Tested)