Configuring and Monitoring Port Security

MAC Lockout

Port Security and MAC Lockout

MAC Lockout is independent of port-security and in fact will override it. MAC Lockout is preferable to port-security to stop access from known devices because it can be configured for all ports on the switch with one command.

It is possible to use MAC Lockout in conjunction with port-security. You can use MAC Lockout to lock out a single address—deny access to a specific device—but still allow the switch some flexibility in learning other MAC Addresses. Be careful if you use both together, however:

If a MAC Address is locked out and appears in a static learn table in port-security, the apparently “authorized” address will still be locked out anyway.

MAC entry configurations set by port security will be kept even if MAC Lockout is configured and the original port security settings will be honored once the Lockout is removed.

A port security static address is permitted to be a lockout address. In that case (MAC Lockout), the address will be locked out (SA/DA drop) even though it’s an “authorized” address from the perspective of port security.

When MAC Lockout entries are deleted, port security will then re- learn the address as needed later on.

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