Add TFTP option to Windows Server 2012 DHCP
This works with Cisco phones, not sure if it works with any others. I only have Cisco phones so I cannot test with any other brand, but I don’t see why it wouldn’t. In your DHCP panel, right click the IPv4 option and select “Set Predefined Options…”.
Click the add button. Fill in the following details:
Now, in your scope options, right click and click configure options
Scroll to the bottom of the list and set the IP address of your TFTP server!