IMPORTANT: DHCP options 128-135 used to configure legacy Mitel IP endpoints have been reclassified as public options by the Internet Engineering Task Force (see RFC 2133 and RFC 3925). To comply with the change, Mitel recommends using either option 43 or 125, depending on the server's ability to support them and on administrator preference. The embedded server supports both options; 125 is the factory-programmed default. The old options can still be used to provide backward compatibility with IP sets that have yet to be upgraded with firmware that supports the new options. After the upgrade, the old options may be removed to prevent future conflicts with standard use or other vendors' use of these options. The following procedure applies to new installations only. For upgrade procedures, see the MiVoice Business Technician's Handbook.
NOTE: 69xx IP Phones do not support DHCP Options 128 through 130.
When you program the DHCP server in MiVoice Business, the following conditions apply.
You must populate the subnets that you want the DHCP server to respond to. By default, the subnet 192.168.1.0 is assigned. If different subnets will be used in your installation, then delete this default subnet.
Configure the DHCP options that you want applied to the subnets. Apply each option to the defined subnets at one of the following scopes: Global, Subnet, or Range. The DHCP server responds with option information to DHCP requests based on the priority of the scope setting. The highest priority is Range, followed by Subnet, and lastly Global. A request from a subnet, or scope, that is not defined will not elicit a DHCP response.
If you deleted the default subnet of 192.168.1.0, the associated DHCP option information for this subnet is ignored. However, you should delete any DHCP options assigned to this subnet as a precautionary measure.
69xx IP Phones must get their firmware from an external TFTP server when there are more than 200 of them on a 3300 ICP controller or 1500 on all MiVoice Business server variants. If you have these devices in your network, configure DHCP option 66 to point the phones to the external server.
When you program the DHCP server on a Windows 2019 server, ensure the following:
The DHCP server is deployed.
Start Server Manager.
On the Manage menu, click Add Roles and Features.
Select Server Roles, and select the DHCP Server check box under Roles.
Download the DHCP Config Helper application from Software Download Center (under the MiVoice Business category).
To program the DHCP server in MiVoice Business (applies to all platforms except Container-based MiVoice Business (cMiVB)), refer to Configuration > DHCP in the Server Manager Help.
To program an external Windows 2019 DHCP server (applies to Container-based MiVoice Business (cMiVB):
In the Windows 2019 server, Start Server Manager.

On the Tools
menu, click DHCP.
The DHCP window is displayed.

In the left pane, navigate to DHCP > server name> IPv4.
Right-click
IPv4, and click New Scope.
The New Scope Wizard window is displayed.

Follow the wizard to enter the following details (skip rest of the wizard windows that are not listed below by clicking Next):
Scope Name (for example, VOIPScope)
IP Address Range
Configure DHCP Options
Select Yes, I want to configure these options now.
Router (Default Gateway)
Domain Name and DNS Servers (if applicable)
Activate Scope
Select No, I will activate this scope later.
Click Finish.
In the left pane, navigate to DHCP > server name> IPv4.
Right-click IPv4, and click Set
Predefined Options.
The Predefined Options and Values window is displayed.

Click Add.
The Option Type window is displayed.

Enter the following, and click OK.
Name - Mitel option
Data type - Encapsulated
Code - 125 or 43
Description - For Mitel phone
In the Windows 2019 server, start the DHCP Config Helper application.
NOTE: You can download the DHCP Config Helper application from Software Download Center (under the MiVoice Business category).

Enter the following:
TFTP Server Address ( sw_tftp ) - FQDN of the TFTP server provided in the welcome e-mail.
Call Server Address [ call_srv ] - FQDN of the call server provided in the welcome e-mail.
VLAN ID [ vlan ] (if applicable)
Diffserv Codepoint (dscp) (if applicable)
Click Update Display.
NOTE: The Update Display button is not available until you specify the mandatory fields.
Click Copy Hex Bytes to clipboard, and past the Hex Bytes to a txt file using the Notepad application.
In the Windows 2019 server, start Windows PowerShell.

Enter the following commands:
netsh
dhcp
server
scope <ip address of the scope>
set optionvalue 125 ENCAPSULATED <paste the Hex Bytes from the txt file)
In the DHCP window, in the left pane, navigate to DHCP > server name > IPv4 > Scope.
Click Scope
Options.
The DHCP Option 125 is displayed on the right side of the pane.
NOTE: If the DHCP Option is not displayed, then on the Action menu, click Refresh.

In the DHCP window, in the left pane, navigate to DHCP > server name > IPv4.
Right-click Scope and click Activate.