Cisco 9800 WLC DHCP Option 43

[Noovi]

Hello Team,

I have wireless setup with Cisco 9800 WLC and we have created DHCP pool on WLC itself due to site restrictions/security purpose.

I have attached snap where in DHCP pool, i have added option 43 and hex value of WLC.

But still APs are not able to join WLC automatically.

Any inputs/Suggestions?

[Flavio Miranda]

Hi @Noovi 

 You may check this document:

" DHCP option 43 is not supported on the internal server. Therefore, the APs must use an alternative method to locate the management interface IP address of the device, such as local subnet broadcast, Domain Name System (DNS), or priming."

https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/config-guide/b_wl_16_10_cg/dhcp-for-wlans.html#Cisco_Concept.dita_cf3a1219-4b1f-432e-8ec5-42ed8a860302

[d-vachhani]

Hi @Flavio Miranda , how do we assign IP address to AP which is wirelessly trying to pair with WLC ? how to setup WLC as internal DHCP server for assigning IP address to CAPWAP APs and after that pair them ?

Thanks. 

[Scott Fella]

@d-vachhani The ap's need to get a ip address first to have any change of joining a controller.  This can be dhcp, or manually configuring an ip address on the ap itself. It is best to have the ap's on the same subnet as the controller since the ap will perform a L2 discovery.  If the AP's are in a different subnet, then you have move configurations you will need to do on the network side for the ap's to obtain a dhcp from the controller and for the ap's to discover the controller.  Having restrictions, is really going to make it hard for you and for the customer to troubleshoot in the future.

[d-vachhani]

Thanks @Scott Fella, my AP and WLC will be on same subnet. Issue I am facing is for initially assign IP address to AP, after that  I hope it will pair with WLC using L2 discovery, do I need to create DHCP server in WLC for initial AP IP address assignment ?