Mike's PBX Cookbook

DHCP Configuration

DHCP Configuration in conjunction with with 1120 VoIP sets.

The DHCP Server

Notice that the Server Options tab has two services activated. This is a system wide field. Anything active in here is active for all scopes.

The first is Option 66: Boot Server. This is the IP address of the TFTP server, the phones will use this address to download configuration and firmware upgrades.

The second is Option 128: Call Server. This option needs to be built. The string always begins with Nortel-i2004-A, followed by the IP address of the node, port number, action, and number of retries. This is entered twice (S1 and S2). If you don't have a second call server, repeat the S1 settings.

For example, enter the following string to configure an IP Phone to use Call Server S1 IP address of, Call Server S2 IP address of, S1 and S2 port number of 4100, S1 and S2 action of 1, and S1 and S2 retry of 5:



For each of the VLAN(s) you created, turn on Option 003 Router, and enter the gateway address for that VLAN. You need the VLAN-A:2. This refers to the VLAN you are in.

Also the scope field is where you make the range of IP address for the IP Phones (left image below).

The 066 and 128 carry over from the Server Options (right image below).

The TFTP server

Use a TFTP server, such as PumpKIN (Mac/Windows) or Solarwinds (Windows), to distribute the following two files:

  1. 1120e.cfg
  2. system.prv

The .cfg file is used for firmware updates. The firmware .bin file needs to be in the same folder. The .prv file can transfere the Call Server IP, NODE ID, and TN to the IP Phone, but is not needed for manual provisioning.

Configuring a TFTP server is not covered here, but is usually pretty straight forward.


The cfg file options are fairly clear.
Version number, filename, etc.
Sercurity mode works with 0.

#Config file: 1120e  C8Q
FILENAME 0624C8Q.bin


'reg' must be lower case.
The next field is the MAC address of the phone (all uppercase, no colons)
s1, 1181 (node #), the sets TN (lscu) separated with the dashes.


Shown below, the shared C:\tftp folder containing the three files required.

Home » Voip » Dhcpcfg