APのWLCの登録プロセス/順序、AP modeについて


APのWLCへの登録はstatic IP アドレスで指定していれば、WLCに登録されて問題なしと思っていたが、商用環境で問題が実際に発生したので、今後のためにメモ。


The AP goes through this process on startup:

  1. The LAP boots and DHCPs an IP address if it was not previously assigned a static IP address.
  2. The LAP sends discovery requests to controllers through the various discovery algorithms and builds a controller list. Essentially, the LAP learns as many management interface addresses for the controller list as possible via:
    1. DHCP option 43 (good for global companies where offices and controllers are on different continents).DNS entry for cisco-capwap-controller (good for local businesses – can also be used to find where brand new APs join) If you use CAPWAP, make sure there is a DNS entry for cisco-capwap-controller.Management IP addresses of controllers the LAP remembers previously.A Layer 3 broadcast on the subnet.Statically configured information.Controllers present in the mobility group of the WLC the AP last joined.
    From this list, the easiest method to use for deployment is to have the LAPs on the same subnet as the management interface of the controller and allow the LAPs Layer 3 broadcast to find the controller. This method must be used for companies that have a small network and do not own a local DNS server.The next easiest method of deployment is to use a DNS entry with DHCP. You can have multiple entries of the same DNS name. This allows the LAP to discover multiple controllers. This method must be used by companies that have all of their controllers in a single location and own a local DNS server. Or, if the company has multiple DNS suffixes and the controllers are segregated by suffix.DHCP option 43 is used by large companies to localize the information by the DHCP. This method is used by large enterprises that have a single DNS suffix. For example, Cisco owns buildings in Europe, Australia, and the United States. In order to ensure that the LAPs only join controllers locally, Cisco cannot use a DNS entry and must use DHCP option 43 information to tell the LAPs what the management IP address of their local controller is.Finally, static configuration is used for a network that does not have a DHCP server. You can statically configure the information necessary to join a controller by the console port and the APs CLI. For information on how to statically configure controller information by use of the AP CLI, use this command:
  3. AP#capwap ap primary-base <WLCName> <WLCIP>

DHCP43 optionがある環境だとそちらを参照されてしまう。


AP modeについて(WLC->APモード)


EWC to CAPWAP AP conversion using the AP CLI

You can convert an EWC to function as CAPWAP by executing a single command from the access point CLI:

AP#ap-type capwap

Note:     The access point will reboot and the AP type will change to NOT EWC CAPABLE. Also, after the AP is converted to CAPWAP, it will no longer participate in the active election process.




To convert an AP running a CAPWAP image to EWC, perform the following steps:


Step 1.          Connect and log in to the Cisco Catalyst 9100 Access Point CLI or console.

Step 2.          Enter enable to go to privileged execution mode.

Step 3.          Enter show version on the access point CLI. From the show version output, you can determine the AP image type and AP configuration and can then proceed with the conversion process.

Step 4.          If the AP image type and AP configuration are not available in the show version output, it means the AP is running a CAPWAP image. To do the conversion, execute the command below:

AP#ap-type EWC tftp://<TFTP Server IP>/< ap image> tftp://<TFTP Server IP>/< WLC image>

Example: AP#ap-type EWC tftp:// tftp://

Step 5.          After the AP reboots, the EWC starts in day 0 and CiscoAirProvision-<MAC> SSID is broadcast. You can then configure it from the wireless configuration wizard.



WLC# wireless ewc-ap ap shell username <admin>



AP# capwap ap ip