Microsoft’s All New Dead Host Configuration Protocol

Who Needs Working DHCP Anyways?

There was yet another issue with patch Tuesday, one which didn’t make itself obvious until the IP leases on clients started to expire and were sometimes unable to renew their IP or get a new one.  To make it more frustrating to figure out, because that’s just what you need from your DHCP servers, the “service might intermittently stop responding after installing this security update.”  Intermittent issues are a nightmare to track down, especially with DNS and DHCP.  The symptoms would not be predictable, some clients would grab a new IP or renew their lease without issues, while other clients would see a failure when trying to get a DHCP provided IP address.

This issue doesn’t effect static IPs, but who in their right mind would want to try to assign a static IP to every existing machine in their environment as well as creating new reservations for each and every new device trying to connect to their network?  Unfortunately that is the the only solution apart from riding the DHCP service on your servers and constantly checking to ensure they are running and restarting them if they are not.  

If you are having brand new DHCP issues, you may want to roll back KB5060842 on any of your servers running Windows Server 2025, 2022, 2019, or 2016.  In fact, you might just want to get rid of that Server 2016 install altogether, this is a good excuse if you can get the budget!  

No news on a permanent fix yet, as Microsoft is still trying to figure out how they broke DHCP in the first place.