Using DHCP Search Domains on Windows DHCP Clients

The DNS Search Domain functionality present in the DHCP Server settings in pfSense® software is only supported by some DHCP clients; pfSense software uses the standard DHCP option 119 mechanism to deliver the search domains to clients which request them.

Support for Option 119 was finally added in Windows 10 version 1803 released in April 2018. Unfortunately, older versions of the Microsoft Windows DHCP client do not support requesting option 119, so no matter which DHCP server is used, clients running older versions of Microsoft Windows can never receive or use a search domain list from DHCP. Upgrade clients to a supported release to use this functionality.


If older clients must use these settings and they cannot be upgraded, the setting can be pushed via GPO instead of DHCP.