Cisco : Reset ASA OS to factory default

Here is a quick how to reset Cisco ASA (Adaptative Security Appliance) to factory default. You will need a serial console access to achieve this task.

1. At early boot process, just hit escape [esc] key when suggested as followed :

And you will end up with the following command prompt :

2. Enter the following command to see what configuration we are running first :

And this should return something like this :

(You should say no about changing the configuration.)

3. Register the default configuration on boot :

The output will look like :

4. Then boot on the default config :

Console output :

5. Enter the privileged access mode :

You will be prompted for a password, just leave it blank.

6. Copy the current default running configuration to be the startup configuration and press enter :

Console output :

7. Enter in configuration mode :

8. Change the “enable” password to a known value :

9. Register the running configuration on boot :

10. Write configuration to memory :

Console output :

11. Restart your device with the following command :

Console ouput :