Standard Break Key Sequence Combinations During Password Recovery

Contents

Introduction
Components Used
Standard Break Key Combinations
Troubleshooting Tips
How to Simulate a Break Key Sequence

Introduction

This document provides standard break key sequence combinations for the most common operating systems, and some troubleshooting tips.

Components Used

This document is not restricted to specific software and hardware versions.

The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.

Standard Break Key Combinations

Software Platform Operating System Try This

Hyperterminal

IBM Compatible

Windows 2000

Ctrl-Break

Hyperterminal (version 595160)

IBM Compatible

Windows 95

Ctrl-F6-Break

Kermit

Sun Workstation

UNIX

Ctrl-\l

Ctrl-\b

MicroPhone Pro

IBM Compatible

Windows

Ctrl-Break

Minicom

IBM Compatible

Linux

Ctrl-a f

ProComm Plus

IBM Compatible

DOS or Windows

Alt-b

Telix

IBM Compatible

DOS

Ctrl-End

Telnet to Cisco

IBM Compatible

N/A

Ctrl-]

Teraterm

IBM Compatible

Windows

Alt-b

Terminal

IBM Compatible

Windows

Break

Ctrl-Break

Tip

Sun Workstation

UNIX

Ctrl-], then Break or Ctrl-c

~#

VT 100 Emulation

Data General

N/A

F16

Windows NT

IBM Compatible

Windows

Break-F5

Shift-F5

Shift-6 Shift-4 Shift-b (^$B)

Z-TERMINAL

Mac

Apple

Command-b

N/A

Break-Out Box

N/A

Connect pin 2 (X-mit) to +V for half a second

Cisco to aux port

N/A

Control-Shft-6, then b

IBM Compatible

N/A

Ctrl-Break

Troubleshooting Tips

  • Problems encountered during password recovery often occur because users do not know what the break key sequence is for the (non-Cisco) software they are using. For software not listed above and for additional information, users should refer to the documentation of their individual software packages.

  • The auxiliary (AUX) port is not active during the boot sequence of a router. Therefore, sending a break through the AUX port does not work. You need to be connected to the console port, and have the following settings:

    9600 baud rate

    No parity

    8 data bits

    1 stop bit

    No flow control

How to Simulate a Break Key Sequence

This is useful if your terminal emulator doesn't support the break key, or if a bug prevents it from sending the correct signal (the hyperterminal under Windows NT used to suffer from this behavior):

  1. Connect to the router with the following terminal settings:

    1200 baud rate

    No parity

    8 data bits

    1 stop bit

    No flow control

    You no longer see any output on your screen. This is normal.

  2. Power cycle (switch off and then on) the router and press the spacebar for 10-15 seconds. This generates a signal similar to the break sequence.

  3. Disconnect your terminal and reconnect with a 9600 baud rate. You should now be in ROM Monitor mode.


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