Mark, Thank you for the suggestion. I just looked and DHCP Proxy is NOT enabled.
So far today, we have had no repeat misbehavior. I am hoping the problem is related to the DHCP server override setting. That would make the most sense. I like when there is a logical answer. Regards, Christina On 08/21/2014 05:35 PM, Mark Duling wrote: > Is the DHCP proxy feature of WLC unchecked? Controller -> Advanced -> DHCP > > We had a case where it was enabled (perhaps the default in early > versions) and it never seemed to matter until some years later due to > reasons I don't even remember. It probably is off, but you might check > it. At the time we had our problems a TAC engineer said something like > "some dhcp servers with firewalls won't work with this setting". > > Just a thought. > > > On Thu, Aug 21, 2014 at 2:27 PM, Christina Klam <[email protected] > <mailto:[email protected]>> wrote: > > I am hoping someone can point me in the correct direction. Two days in > a row, our wireless controllers (4404 and wism2) have stopped sending > the DHCP requests for clients for just one of our WLAN. This WLAN is > open and is used as the Multicast VLAN for our two 802.1X WLANs. > > Recent Changes: > 1. Tuesday morning, we replaced our ISC DHCP servers with Infoblox. > 2. As part of that change, we had to change the dhcp server settings on > all of the dynamic interfaces. In classic mode of Prime, you are not > allowed to enter just one dhcp address. So, on the controllers > themselves, I manually updated the list of dhcp servers for all of the > dynamic interfaces except the open one, ias-144. I was not allowed to > change the dhcp settings on ias-144 because it was in use. As we were > getting near the end of our window, I setup the dhcp override in the > corresponding WLAN. (I later remembered it was "in use" as the > Multicast VLAN.)) > 3. Wednesday, about 25 hours after the dhcp server change, clients were > unable to get an ip address. We "fixed" this issue by disabling the > WLAN, removing it as the Multicast VLAN, and replacing its dynamic > interface using a Prime's Lifecycle Theme template. > 4. Today at 13:21, the problem reoccurred. I removed the dhcp override > option as it was no longer needed. That didn't help. We then disabled > and re-enabled the WLAN. After doing so, clients were able to get their > dhcp addresses. > > > Has anyone else seen this behavior? The ip helper-address is the same > for all of the WLANs on the 6509 and on the controllers. All of the > dynamic interfaces look the same on the controllers. > > Thank you for your help, > -- > Christina Klam > Network Engineer > Institute for Advanced Study > Email: [email protected] <mailto:[email protected]> > > Einstein Drive Telephone: 609-734-8154 <tel:609-734-8154> > Princeton, NJ 08540 Fax: 609-951-4418 <tel:609-951-4418> > > ********** > Participation and subscription information for this EDUCAUSE > Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > > > ********** Participation and subscription information for this EDUCAUSE > Constituent Group discussion list can be found at > http://www.educause.edu/groups/. > -- Christina Klam Network Engineer Institute for Advanced Study Email: [email protected] Einstein Drive Telephone: 609-734-8154 Princeton, NJ 08540 Fax: 609-951-4418 ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
