Question

Which commands are used to re-enable a port that has been disabled as a result of a port security violation?

Answer 1

To re-enable a port after a security violation on a Cisco network device, enter privileged EXEC mode, then go to global configuration mode, shut down, and re-enable the interface by using the 'shutdown' and 'no shutdown' commands. Clearing the security violation count might also be necessary.

Step-by-step explanation:

The commands used to re-enable a port that has been disabled as a result of a security violation typically involve entering the network device's command-line interface and executing a specific set of commands.

For Cisco devices, the procedure is generally as follows:

1. Enter privileged EXEC mode by typing 'enable' at the prompt.
2. Type 'configure terminal' to enter global configuration mode.
3. Select the interface that has been disabled by a security violation using the command 'interface [interface_name]', where [interface_name] is the name of the interface (e.g., FastEthernet0/1).
4. To manually re-enable the port, use the command 'shutdown' followed by 'no shutdown'.
5. Optionally, if port security has been set to protect or restrict, the violation might not disable the port but rather drop traffic. If the security violation count needs to be cleared, use the command 'clear port-security sticky interface [interface_name]' or 'clear port-security all' if applicable.

These commands first shut down the interface and then bring it back up, which effectively re-enables the port. These steps can vary depending on the device manufacturer and the network setup.