Resetting the Configuration File When the Router Is Inaccessible

You can use the router's RESET CONFIG button to restore the router's configuration file when the current one is faulty or fails. You can also change the default behavior of the RESET CONFIG button.

Using the RESET CONFIG Button

If a configuration fails or denies management access to the router, you can use the RESET CONFIG button to restore the router to the factory default configuration or a rescue configuration. For example, if someone inadvertently commits a configuration that denies management access to a router, you can delete the invalid configuration and replace it with a rescue configuration by pressing the RESET CONFIG button. The button is recessed to prevent it from being pressed accidentally.

The rescue configuration is a previously committed, valid configuration. You must have previously set the rescue configuration through the J-Web interface or the CLI.

To press the RESET CONFIG button, insert a small probe (such as a straightened paper clip) into the pinhole on the front panel (see Figure 8 and Figure 9):

• By default, pressing and quickly releasing the RESET CONFIG button loads and commits the rescue configuration through the J-Web interface or the CLI. (For details, see the J-Web Interface User Guide and the JUNOS CLI User Guide.)
• By default, pressing and holding the RESET CONFIG button for 15 seconds or more—until the STATUS LED blinks red—deletes all configurations on the router, including the backup configurations and rescue configuration, and loads and commits the factory configuration. (For details about the factory default settings, see the JUNOS Software Administration Guide.)

Changing the RESET CONFIG Button Behavior

You can change the default operation of the the RESET CONFIG button by limiting how the button resets the router:

• To prevent the RESET CONFIG button from setting the router to the factory default configuration and deleting all other configurations, enter the following command. You can still press and quickly release the button to reset it to the rescue configuration.

  user@host# set chassis config-button no-clear

• To prevent the RESET CONFIG button from setting the router to the rescue configuration, enter the following command. You can still press and hold button for 15 seconds or more to reset the router to the factory defaults.

  user@host# set chassis config-button no-rescue

• To disable the button and prevent the router from resetting to either configuration, use the following command:

  user@host# set chassis config-button no-clear no-rescue

The no-rescue option prevents the RESET CONFIG button from loading the rescue configuration. The no-clear option prevents the RESET CONFIG button from deleting all configurations on the router.

To return the function of the RESET CONFIG to its default behavior, remove the config-button statement from the router configuration.