Meru Technical Note - Do the AP and the controller need to be in the same subnet?
Do the AP and the controller need to be in the same subnet?
Scope
KB ARTICLE TYPE: Troubleshooting
RELATED PRODUCTS: Controller,AP
RELATED SOFTWARE VERSIONS:ALL
KEYWORDS: ESS, controller, SSID
Solution
Meru AP is capable of discovering the controller, even if the controller is on a different subnet than the AP.The default sequence is an AP boots using Layer 2 discovery preferred. If the Layer 2 discovery fails, the AP will perform a DHCP request to retrieve an IP address, gateway, and DNS server. The AP will then try to perform a Layer 3 discovery, first by checking the static configuration of the controller IP/Name in the AP, second by getting the controller IP from DHCP option 43 and finally a DNS lookup of the hostname "wlan-controller".This entry has to have been pre-configured on the DNS server for the AP to successfully retrieve the address of a Meru controller.
APs separated from the controller by one or more routers should configure L3 discovery ( ap-connectivity l3-preferred ).This can be done by configuring a static IP address of the designated controller or by updating the DNS with the default hostname "wlan-controller."