Learned addresses

In the following two cases, a port in Static learn mode retains a learned MAC address even if you later reboot the switch or disable port security for that port:

The port learns a MAC address after you configure the port for Static learn mode in both the startup-config file and the running-config file (by executing the write memory command).
The port learns a MAC address after you configure the port for Static learn mode in only the running-config file and, after the address is learned, you execute write memory to configure the startup-config file to match the running-config file.

To remove an address learned using either of the preceding methods, do one of the following:

Delete the address by using no port-security <port-number> mac-address <mac-addr>.
Download a configuration file that does not include the unwanted MAC address assignment.
Reset the switch to its factory-default configuration.