Troubleshooting The Access Point To Cisco Controller Join Process - Cisco Catalyst 9136I Series Hardware Installation Manual

Troubleshooting the Access Point to Cisco Controller Join Process

Troubleshooting the Access Point to Cisco Controller Join
Process
Note
Access points can fail to join a controller for many reasons—a RADIUS authorization is pending, self-signed
certificates are not enabled on the controller, the access point and the controller regulatory domains don't
match, and so on.
Controller software enables you to configure the access points to send all CAPWAP-related errors to a syslog
server. You do not need to enable any debug commands on the controller because all of the CAPWAP error
messages can be viewed from the syslog server itself.
The state of the access point is not maintained on the controller until it receives a CAPWAP join request from
the access point. Therefore, it can be difficult to determine why the CAPWAP discovery request from a certain
access point was rejected. In order to troubleshoot such joining problems without enabling CAPWAP debug
commands on the controller, the controller collects information for all the access points that send a discovery
message to it and maintains information on any access points that have successfully joined it.
The controller collects all the join-related information for each access point that sends a CAPWAP discovery
request to the controller. Collection begins with the first discovery message received from the access point
and ends with the last configuration payload sent from the controller to the access point.
When the controller is maintaining join-related information for the maximum number of access points, it does
not collect information for any more access points.
An access point sends all the syslog messages to the IP address 255.255.255.255 by default.
You can also configure a DHCP server to return a syslog server IP address to the access point using option 7
on the server. The access point then starts sending all the syslog messages to this IP address.
When the access point joins a controller for the first time, the controller sends the global syslog server IP
address (the default is 255.255.255.255) to the access point. After that, the access point sends all the syslog
messages to this IP address until it is overridden by one of the following scenarios:
• The access point is still connected to the same controller, and the global syslog server IP address
• The access point is still connected to the same controller, and a specific syslog server IP address has been
• The access point is disconnected from the controller and joins another controller. In this case, the new
• Whenever a new syslog server IP address overrides the existing syslog server IP address, the old address
Cisco Catalyst 9136I Series Access Point Hardware Installation Guide
26
As specified in the Cisco Wireless Solutions Software Compatibility
running controller software Cisco IOS-XE 17.7.1 or later release to support C9136I AP.
configuration on the controller has been changed using the config ap syslog host global
syslog_server_IP_address command. In this case, the controller sends the new global syslog server IP
address to the access point.
configured for the access point on the controller using the config ap syslog host specific Cisco_AP
syslog_server_IP_address command. In this case, the controller sends the new specific syslog server IP
address to the access point.
controller sends its global syslog server IP address to the access point.
is erased from persistent storage, and the new address is stored in its place. The access point also starts
Troubleshooting
Matrix, ensure that your controller is