WLAN DHCP Mapping Inheritance Level/AP no access issue

[Valkyrie3]

I've a couple of issues with a Cisco Wireless system that I've spent a while hunting through the documentation for and can't find an answer.  I have my standard CCNA but I've still a lot to learn on the wireless side.

The first problem I'm having with a Cisco Wireless controller is I'm trying to configure a new AP on the system and I can match all the settings to an existing AP except when I open the AP go to Flexconnect, then Central DHCP Processing.  On the existing APs the Inheritance Level is varies between Wlan and AP for each of the WLAN SSIDs where they're all set to Wlan on the new one.  I can't change the option on this screen so I've had a look in the Flexconnect group settings but I can see options for Central DHCP but not the inheritance level.  I also noticed an existing AP is sitting in the default Flexconnect group which has the different inheritance level settings suggesting it's not being configured within the Flexconnect group.  

The AP I've configured appears to work fine but I'd like to know how this setting is configured and what it's used for.

The other issue with the existing APs (AIR-AP3802I-E-K9 on Cisco 3650's) is that occasionally (every few months or so) a wireless device can connect to the AP but then can't access anything else.  The AP seems to show normally on the controller and I can't see any errors for it, restarting the AP resolves the issue and there's no other access problems on the same switches, there doesn't seem to be a pattern with the APs it occurs to apart from tends to be those in heavier use.  Is there anything to look for that can cause this?  Restarting the AP isn't a big deal but it can be tricky to find which one is actually causing the problem in areas with many APs.

Thanks for any advice.

[JPavonM]

Regarding your DHCP issue, check AP switchport side is configured with proer VLANs, native VLAN is been used to communicate with WLC in cetrnal DHCP to assign IP address to clients on the SSIDs, so check DHCP proxy in the WLC side for the L3 switches behind it.

Here you have some good guides to start with and know how it works:
https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-5/Enterprise-Mobility-8-5-Design-Guide/Enterprise_Mobility_8-5_Deployment_Guide/ch7_HREA.html

https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-7/Flex_7500_DG.html

https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-5/config-guide/b_cg85/flexconnect.html

[Valkyrie3]

Thanks for the response, there's no actual DHCP issue I can see as the wireless devices can connect through the AP and pick up their address.  I've tested using an existing AP port and these DHCP settings don't change, I've been through the WLAN guides but I can't find any reference to what this inheritance level setting does nor how to change it.  I can find some information on the Central DHCP/Override DNS/NAT-PAT settings which are the ones I can change and set in the Flexconnect group but not the inheritance level.

Edit: Just to clarify, you can see the inheritance level setting at the bottom of this guide but there doesn't seem to be any option to change it or refer to how that's done unless I'm missing it:

https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/211325-FlexConnect-Central-DHCP-Configuration-E.html

[Rich R]

If it's a problem that goes away after a reboot then 99.999% it's a software bug.
What model of WLC are you using?
What version of software is the WLC running?

[Valkyrie3]

It's a Cisco Virtual Wireless Controller on version 8.10.130.0 which looks to be a few versions out of date now so you're probably correct there, I'll look into updating before investigating that problem any further.

[Valkyrie3]

I've been having a good look through the documentation but I can't find anything about these settings.  I found an AP that had been left in the default AP group and moved it into the new one I created, this one had the inheritance levels varying between WLAN and AP however it kept these settings when moved suggesting they're not coming from the Flexconnect group settings.

I thought I'd try using the remove option for the new AP on one of the WLANs (remove is the only option on the drop down) but it failed with the error 'Deletion failed: This entry is not present at the AP level' suggesting it's coming from the WLC somewhere.  I went back to the WLAN definitions but I can't see anything relevant, the new AP is a member of one of the existing AP groups.

I had a look through the WLC backup config but I can't see these options either.  I've also tried connecting to an AP directly over the command line with the thought I could back up the config of an existing AP, modify it slightly and restore it to a new AP to see if that worked.  However I could only find commands for standalone APs, none that worked for the WLC based AP and the usual Cisco IOS type commands worked.  What would be the correct command to use here and would this be any use?  I ran the command to show the AP config but I couldn't see anything that was WLAN specific that would match what I'm trying to find.

The AP itself seems to be working normally and no DHCP issues but I'd like to know how to set this option as I might find something else I'm missing.