Password Recovery Facts

Password recovery is the process of discovering or resetting forgotten router passwords. The exact process you use to recover lost passwords depends on the switch model. Listed below are the general steps you would take for the 2960 switch:

  1. Establish a console connection to the switch.
  2. Unplug the power cable.
  3. Hold down the mode button while reconnecting the power cable to the switch. Release the mode button when the SYST LED blinks amber and then turns solid green. When you release the mode button, the SYST LED blinks green.
  4. Type the flash_init command.
  5. Type the load_helper command.
  6. Type the dir flash: command. Note: make sure to include the colon (:).
  7. Type rename flash:config.text flash:config.old to rename the configuration file.
  8. Type the boot command to restart the system.
  9. Enter yes to terminate autoinstall.
  10. Enter n at the prompt to abort the initial configuration dialog.
  11. Type enable to enter enable mode.
    • To save the previous settings and configurations of the switch, type rename flash:config.old flash:config.text
    • To overwrite the settings and configurations of the switch, type copy flash:config.text system:running-config to copy the configuration file into memory.
      Note:       the configuration file is now reloaded.
  12. Enter configuration mode to change the passwords.
  13. In global EXEC mode, type copy run start to save the changes.

To recover passwords on most routers, you need to modify the configuration register to bypass the startup-config file and boot the router with a limited IOS version. You can then load the existing startup-config file and view or modify the current password settings. The exact process you use to recover lost passwords depends on the router model. Listed below are the general steps you would take for the 1800 series routers:

  1. Establish a console connection to the router.
  2. At the prompt, type show version. Record the value for the configuration register (usually 0x2102).
  3. Turn the router off and on.
  4. Within 60 seconds, use the keyboard to send a break sequence to the router. For a Windows system, the break sequence is typically one of the following:
    • Break + F5
    • Shift + F5
    • ^$B (Shift + 6, Shift + 4, Shift + b)
  5. Type confreg 0x2142 to change the configuration register setting.
  6. Type reset or i to reboot. With the configuration register changed, the router reboots bypassing the startup-config file.
  7. The router will automatically enter Setup mode. At this point you can:
    • Use Setup mode to configure the router (including the passwords).
    • Quit Setup mode (using Ctrl + C) and change only the existing passwords.
      1. Type enable to enter privileged EXEC mode.
      2. Type copy start run to load the startup-config file.
      3. Enter configuration mode to change the passwords.
      4. Type config-register 0x2102 to change the configuration register back to the default.
      5. Exit configuration mode and use copy run start to save the changes to the passwords.
  8. Use the reload command to restart the router normally.

 

Credit: Testout 640-802 CCNA Notes