Wednesday, 6 April 2011

Password Recovery Procedure for the Cisco 1700 Series Routers

Introduction:
                      

                                                                                   


This document describes the procedure to recover an enable password or enable secret password. These passwords are used to protect access to privileged EXEC and configuration modes. The enable password can be recovered but the enable secret password is encrypted and can only be replaced with a new password with the help of the procedure in this document.

Note: 

This password recovery procedure works for these Cisco products:

·         Cisco 4700
·         Catalyst 2948G-L3
·         Cisco 827
·         Cisco AS5x00
·         Catalyst 4840G
·         Cisco uBR900
·         Cisco 6x00
·         Catalyst 4908G-L3
·         Cisco 1003
·         Cisco 7000 (RSP7000)
·         Catalyst 5500 (RSM)
·         Cisco 1004
·         Cisco 7100
·         Catalyst 8510-CSR
·         Cisco 1005
·         Cisco 7200
·         Catalyst 8510-MSR
·         Cisco 1400
·         Cisco 7500
·         Catalyst 8540-CSR
·         Cisco 1600
·         Cisco uBR7100
·         Catalyst 8540-MSR
·         Cisco 1700
·         Cisco uBR7200
·         Cisco MC3810
·         Cisco 2600
·         Cisco uBR10000
·         Cisco NI-2
·         Cisco 3600
·         Cisco 12000
·         Cisco VG200 Analog Gateway
·         Cisco 4500
·         Cisco LS1010
·         Route Processor Module
·         Cisco 1800
·         Cisco 2800
·         Cisco 3800

Prerequisites

Requirements

There are no specific requirements for this document.

Conventions

For more information on document conventions, see the Cisco Technical Tips Conventions.

Step-by-Step Procedure

To recover your password, complete these steps:
1.     Attach a terminal or PC with terminal emulation to the console port of the router.
Use these terminal settings:
o    9600 baud rate
o    No parity
o    8 data bits
o    1 stop bit
o    No flow control
For more information on cabling and details about how to connect a terminal to the console port or the AUX port, visit these links:
o    Cabling Guide for Console and AUX Ports on Cisco Routers.
o    Connect a Terminal to Catalyst 2948G-L3, 4908G-L3, and 4840G Series Switches.
o    Catalyst 8510CSR, and 8540CSR Switches Console Port Pinouts.
2.     If you still have access to the router, type show version , and record the setting of the configuration register. It is usually 0x2102 or 0x102.
For a sample output of the show version command, refer to the Example of Password Recovery Procedure section.
3.     If you do not have access to the router (because of a lost login or TACACS password), you can safely assume that your configuration register is set to 0x2102.
4.     Use the power switch to turn off the router, and then turn it back on.
Important: To simulate step 4 on a Cisco 6400, pull out and then replace the Node Route Processor (NRP) or Node Switch Processor (NSP) card.
Important: To simulate step 4 on a Cisco 6x00 using NI-2, pull out and then replace the NI-2 card.
5.     Press Break on the terminal keyboard within 60 seconds of the power-up to put the router into ROMMON.
If the break sequence does not work, see Standard Break Key Sequence Combinations During Password Recovery for other key combinations.
6.     Type confreg 0x2142 at the rommon 1> prompt to boot from Flash without loading the configuration.
7.     Type reset at the rommon 2> prompt.
The router reboots, but ignores its saved configuration.
8.     Type no after each setup question, or press Ctrl-C to skip the initial setup procedure.
9.     Type enable at the Router> prompt.
You are taken to the enable mode, and the Router# prompt appears.
10.  Important: Type configure memory or copy startup-config running-config to copy the nonvolatile RAM (NVRAM) into memory.
Do not type configure terminal .
11.  Type write terminal or show running-config .
The show running-config and write terminal commands show the configuration of the router. In this configuration you see under all the interfaces the shutdown command, which means all interfaces are currently shutdown. Also, you can see the passwords (enable password, enable secret, vty, console passwords, and so on), either in encrypted or unencrypted format. The unencrypted passwords can be re-used, the encrypted ones will have to be changed with new passwords.
12.  Type configure terminal and make the changes.
The prompt is now hostname(config)#.
For example, type enable secret <password> to change the enable secret password.
13.  Issue the no shutdown command on every interface that is used.
If you issue a show ip interface brief command, ensure that every interface that you want to use is "up up".
14.  Type config-register 0x2102, or the value you recorded in step 2.
15.  Press Ctrl-Z or end to leave the configuration mode.
The prompt is now changed to hostname#.
16.  Type write memory or copy running-config startup-config to commit the changes. 

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