Incorrect server port number on the access device
Symptom
After a user passes the portal authentication, you cannot force the user to log off by executing the portal delete-user command on the access device, but the user can log off by using the disconnect attribute on the authentication client.
Analysis
When you execute the portal delete-user command on the access device to force the user to log off, the access device actively sends a REQ_LOGOUT message to the portal server. The default listening port of the portal server is 50100. However, if the listening port configured on the access device is not 50100, the destination port of the REQ_LOGOUT message is not the actual listening port on the server, and the portal server cannot receive the REQ_LOGOUT message. As a result, you cannot force the user to log off the portal server.
When the user uses the disconnect attribute on the client to log off, the portal server actively sends a REQ_LOGOUT message to the access device. The source port is 50100 and the destination port of the ACK_LOGOUT message from the access device is the source port of the REQ_LOGOUT message so that the portal server can receive the ACK_LOGOUT message correctly, no matter whether the listening port is configured on the access device. The user can log off the portal server.
Solution
Use the display portal server command to display the listening port of the portal server configured on the access device and use the portal server command in the system view to modify it to make sure that it is the actual listening port of the portal server.