•An access point running software release 5.2 or later has been newly deployed.
•An existing access point running software release 5.2 or later has been reset after clearing the configuration.
If any of these conditions are met and the access point has not yet joined a controller, 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 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 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 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.
•The access point is still connected to the same controller, and a specific syslog server IP address has been 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.
•The access point is disconnected from the controller and joins another controller. In this case, the new controller sends its global syslog server IP address to the access point.
•Whenever a new syslog server IP address overrides the existing syslog server IP address, the old address is erased from persistent storage, and the new address is stored in its place. The access point also starts sending all syslog messages to the new IP address provided the access point can reach the syslog server IP address.
You can configure the syslog server for access points and view the access point join information only from the controller CLI.
A detailed explanation of the join process is on Cisco.com at the following URL:
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