Cisco: Reset a switch password while keeping its configuration

Have you ever needed to log in to a Cisco switch and change its configuration, only to find that you did not have the password? The person responsible may be on vacation or out of the office, or you may have forgotten it.

A few months ago, I had a failing network segment in a production area and needed to act quickly. I found a spare switch, but could not log in.

Reset the password and keep the configuration

The screenshots below show how I reset the password while keeping the VLAN and switch configuration. Power on the switch, connect a console cable and follow these steps:

Press CRTL-C to stop the process. You are now at the "switch:" prompt.

Type flash_init and press Enter. Type load_helper and press Enter to load the basic IOS.

Type rename flash:config.text flash:config.backup to rename the current configuration file as a backup. Type boot to reload the switch.

Choose no for the initial configuration.

Run Rename flash:config.backup config.text and copy flash:config.text system:running-config. You can now add or change the usernames or enable secret. These steps got the spare switch up and running in 15 minutes.