Configuring Whether to Log Out Users If an Interface Goes Down

Context

If an interface goes down due to an interface fault or a direct link fault, the users on the interface are logged out. When the fault is rectified and the interface goes up, the users go online through the interface again. If an interface frequently alternates between up and down due to an interface fault or a direct link fault, the users go online and offline through the interface frequently. To prevent this issue, run the user-policy interface-down command to configure a policy for online users when an interface goes down. The policy can be forcibly logging out the users or keeping the users online.

Procedure

Configure whether to log out users globally if the access interface goes down.
1. Run system-view
  
  The system view is displayed.
2. Run user-policy interface-down { offline | online }
  
  A policy is configured and applied to online users if an interface goes down. The policy can be forcibly logging out the users or keeping the users online.
Configure whether to log out users on an interface if the access interface goes down.
1. Run system-view
  
  The system view is displayed.
2. Run interface interface-type interface-number [ .subinterface-number ]
  
  A sub-interface is created, and the sub-interface view is displayed.
3. Run commit
  
  The configuration is committed.
4. Run bas
  
  BAS is enabled on the interface, and the BAS interface view is displayed.
5. Run either of the following commands:
  - To configure an access type and its relevant attributes for Layer 2 access users, run the access-type layer2-subscriber [ bas-interface-namebname | default-domain { pre-authenticationpredname | authentication [ force | replace ] dname } ^* | accounting-copyradius-serverrd-name ] ^* command.
  - To configure an access type and its relevant attributes for Layer 3 access users, run the access-type layer3-subscriber [ default-domain { pre-authenticationdname | authentication [ force | replace ] dname } ^* ] command.
6. Run user-policy interface-down { offline | online }
  
  A policy is configured and applied to online users if the BAS interface goes down. The policy can be forcibly logging out the users or keeping the users online.
- If the user-policy interface-down command is run in both the system view and the BAS interface view, whether users are logged out if the BAS interface goes down depends on the configuration on the BAS interface, and whether users are logged out if another BAS interface goes down depends on the configuration in the system view.
- If the policy configured using the user-policy interface-down online command is to keep users online if an interface goes down, the logout detection mechanisms, including ARP probe and PPP keepalive, configured for users still take effect. Specifically, if a detection fails, the users are forcibly logged out.