Monday, September 13, 2010

How to Reset the Password(s) on a Linksys SRW248G4 Switch

  1. Connect to the Serial port on the back of the switch with a serial cable. (Putty on Windows works well)
  2. The defaults for connecting to the serial port are 38400 baud, 8 data bits, no parity, 1 stop bit, no flow control.
  3. Confirm that you have an active serial connection by pressing enter a couple of times. You should receive a login screen
  4. Once you have successfully connected to the serial port restart the switch by unplugging the power. (Either from back or from the power strip, my preferred method is the back)
  5. The switch will start its POST process.
  6. Look for the line “Autoboot in 2 seconds - press RETURN or Esc. to abort and enter prom.” (Please note: Do not hold down Esc. or Enter. Only press it once.)
  7. You will know that you interrupted the boot sequence when you are prompted with a startup menu. Select option 3 “Password Recovery Procedure”.
  8. The screen will display “The current password will be ignored!”. Press Enter to reboot the switch.
  9. Once the switch has restarted login with the default admin user and no password. This will work on either the terminal or the web interface. Proceed to create / modify users and passwords. This does not reset the rest of the configuration, just user accounts.
  10. Once you have your new credentials reboot the switch again. Document the credentials.
  11. Verify that your new credentials work by logging into either the web interface for the command line interface.
  12. Disconnect the cable and store it safely.
This is the second time I have required these instructions, so I am posting them here for safe keeping. The last time I did this I removed the default account and setup individual accounts, and then promptly forgot everything about it. This is why documentation is so critical.