The below details how to recover a Cisco device such as a switch or router if you have forgotten or don’t have the password. You will need physical access to the console port
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WARNING: By doing this you may loose any configuration on the router.
- Physically connected to the console port using a tool such as Putty
- Power on the Cisco device
- Press the Break key on your keyboard. If you are using a laptop or keyboard without a dedicated break key try FN + Ctrl + B or Ctrl + FN + F11
- You should see the prompt change to rommon
- At the rommon> prompt type confreg 0x2142 and press enter
- Enter reset and press enter
Info: confreg 0x2142 instructs the router/switch not to load the startup configuration on the next reboot. As the configuration holds the passwords, we will not be prompted for them.
- Wait for the router/switch to fully reboot
- When asked if you “Would you like to enter the initial configuration” type no and press enter
- At the router> prompt enter enable and press enter
- Type conf t and press enter
- Type config-register 0x2102 and press enter
Info: config-register 0x2102 puts the router/switch back into its normal mode. Don’t reboot yet
To start will a clean configuration / factory default
- Type copy run start and press enter
- Type exit and press enter
- Type reload and press enter to restart if a nice clean config
If you want to keep your previous configuration and just change the password(s)
Things are a bit more involved here but if you have experience of basic Cisco configuration you will see where I am going.
- Type copy start run to copy the startup configuration in memory and press enter This will reload your previous config passwords an all.
- Now you can go through the configuration and change any passwords you need to, for example to change the enable secret password you would type enable secret <new_password> and press enter. Change your console, ssh and any others you need to
- Type copy run start and press enter to save your changes
- Type exit and press enter
- Type reload and press enter to restart the router/switch with your amended credentials.
