Hi there, We're running into an interesting problem with several of our sites - I'm not sure if it's the Cisco LWAPs or Server 2008 R2 being a bit odd. Essentially, we have a static reservation for our WAPs that allows them to contact the LWAP controller and do all the wireless good that they were intended to do. The problem is that for some reason or another, the DHCP databases on our branch servers (the ones handing out addresses to the LWAPs) goes inconsistent and only for the LWAP's IP. When this happens and the LWAP tries to renew its address, the server says no, it's in use, and the LWAP requests again. This happens at a lightning fast pace and effectively brings down the network. I haven't had the chance to do any great amount of sniffing on the networks during this time since they're mostly remote sites and the network is unusable when it occurs. Anyone run into a problem similar to this before? - Liam

Found this article: http://support.microsoft.com/kb/981776. Seems to be a bit of a sidestep from what I'm seeing as the reservation isn't deleted, it's more just not allowing the IP to be assigned.

In looking at our DHCP logs, it seems that the AP releases its IP just before the problem happens. Once it tries to renew, the DHCP server spams NACKs. Hotfixes ho!

Hi Liam, Thanks for posting here. I’d suggest configuring a unique static IP address that falls within the exclusion range of the DHCP scope for AP devices instead of setting reservation and obtaining address form DHCP server in this scenario. Configure Wireless AP Settings http://technet.microsoft.com/en-us/library/dd282993(WS.10).aspx Thanks. Tiger LiPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Liam, Please feel free to let us know if the information was helpful to you. Thanks, Tiger Li TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.comPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Tiger, While having it configured with a static IP definitely negates the need to sort out the DHCP problem, it doesn't address our requirement for easy install and configuration. I'll keep you posted as to how the hotfix works out. Cheers! - Liam

The problem did crop up again after the hotfix, but has been non-existent since SP1 for R2.