The following fixes in DHCP Server for Windows Server 2012 have been released as part of Windows rollup update KB 2919393
Issue no 1: DHCP Failover server issues reserved IP address to a client with a different MAC address
This issue pertains to the case when a DHCP Scope which is a part of a failover relationship has an exclusion range and a reservation exists in the scope for one of the IP addresses within the exclusion range. The sequence of events leading to this issue is as follows:
With time this may lead to many clients stuck in DISCOVER-OFFER-REQUEST-NAK cycle and losing network connectivity.
Issue no 2: Some IP addresses are perpetually stuck in BAD ADDRESS state on one of the DHCP failover servers while in Active state on the other server. DHCP Server admin channel contains BINDING ACK reject events 20291 and 20292 for these IP addresses
Now when the update of BAD_ADDRESS to Active state is sent to the partner server, the BINDING update is rejected leading to inconsistency between the 2 DHCP servers.
Both these issues have been fixed in the rollup update for Windows Server 2012 in KB 2919393. The same fixes are in the works for Windows Server 2012 R2. This article will be updated when the KB for 2012 R2 is released.
DHCP failover relation need not be recreated to apply this patch. DHCP server restart is required.
Thanks, I noticed a million of these events on my setup, mostly from the WIFI scopes, will test the R2 patch once is outThxMartin
Why can't I find anything regarding these two fixes in KB2919393? Is there other fixes regarding the DHCP server 2012 HA in KB 2919393? The two problems mentioned above have been a problem since the switch to DHCP server 2012 HA, so they are very welcome.Regards,Peter Jakobsenphj@aalborg.dk
Hi Peter, the KB 2919393 will be updated with details of the DHCP failover fixes. There are no other DHCP server fixes in 2919393.
Any timeframe as to when the hotfix will be available for DHCP server 2012 R2?
Hi Mike, the plan for release of these fixes for DHCP server in 2012 R2 is in the works. We will post an update once its finalized.