Password Recovery Procedure for the Cisco Catalyst 8540 Multiservice Switch Router [Cisco Catalyst 8500 Series Multiservice Switch Routers]

Document ID: 24000

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Password Recovery Procedure for the Cisco Catalyst 8540 Multiservice Switch Router

Introduction

This document describes the procedure for recovering enable password or enable secret passwords. These passwords are used to protect access to privileged EXEC and configuration modes. The enable password password can be recovered, but the enable secret password is encrypted and can only be replaced with a new password using the procedure below.

Before You Begin

Conventions

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

Prerequisites

There are no specific prerequisites for this document.

Step-by-Step Procedure

Follow this procedure to recover the enable password or enable secret passwords.

Attach a terminal or PC with terminal emulation to the console port of the router. Use the following terminal settings:
```
9600 baud rate 
No parity 
8 data bits 
1 stop bit 
No flow control
```
For additional information on cabling and connecting a terminal to the console port or the AUX port, refer to the following documents:
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. Click here to see the output of a show version command.
If you don't have access to the router (because of a lost login or tacacs password), you can safely consider that your configuration register is set to 0x2102.
Using the power switch, 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.

To simulate step 4 on a Cisco 6x00 using NI-2, pull out and then replace the NI-2 card.
Press Break on the terminal keyboard within 60 seconds of the power-up to put the router into ROMMON.

If the break sequence doesn't work, see Standard Break Key Sequence Combinations During Password Recovery for other key combinations.
Type confreg 0x2142 at the rommon 1> prompt to boot from Flash without loading the startup configuration from the nonvolatile RAM (NVRAM).
Type reset at the rommon 2> prompt.

The router reboots but ignores its saved configuration.
Type no after each setup question or press Ctrl-C to skip the initial setup procedure.
Type enable at the Router> prompt.

This puts you in enable mode where you can see the Router# prompt.
Important: Type configure memory or copy startup-config running-config to copy the NVRAM into memory. Do not type configure terminal or copy running-config startup-config or write memory. This erases the router configuration stored in the NVRAM.
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 have to be replaced with new passwords.
Type configure terminal and make the changes.

The prompt is now hostname(config)#.
Type enable secret < password > to change the enable secret password, for example.
Issue the no shutdown command on every interface that is used. If you issue a show ip interface brief command, once you exit the configuration mode (Ctrl-z), every interface that you want to use should be "up up".
Type config-register 0x2102, or the value you recorded in step 2. This makes the router load the startup configuration from the NVRAM during the next reload.
Press Ctrl-z or End to leave the configuration mode.

The prompt is now hostname#.
Type write memory or copy running-config startup-config to commit the changes.

Sample Output

The sample output shown here is the result of the password recovery procedure on a Cisco 4700 Series Router. Even if you are not using a 4700 router, this example should be almost exactly what you experience on your device.

Router>enable

Password:

Password:

Password:

% Bad secrets

Router>show version  
Cisco Internetwork Operating System Software
IOS (tm) 4500 Software (C4500-IS-M), Version 12.2(10b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 11-Jul-02 17:29 by pwade
Image text-base: 0x60008948, data-base: 0x60C74000

ROM: System Bootstrap, Version 5.2(7b) [mkamson 7b], RELEASE SOFTWARE (fc1)

     BOOTLDR: 4500 Software (C4500-BOOT-M), Version 11.3(10), 
     RELEASE SOFTWARE (fc1)

Router uptime is 0 minutes

     System returned to ROMby reload at 17:34:58 UTC Tue Aug 1 1995

     System image file is "flash:c4500-is-mz.122-10b.bin"

cisco 4700 (R4K) processor (revision B) with 32768K/16384K bytes of memory.

     Processor board ID 02169303

     R4600 CPU at 133Mhz, Implementation 32, Rev 2.0, 512KB L2 Cache

     G.703/E1 software, Version 1.0.

     Bridging software.

     X.25 software, Version 3.0.0.

     6 Ethernet/IEEE 802.3 interface(s)

     8 Serial network interface(s)

     128K bytes of non-volatile configuration memory.

     8192K bytes of processor board System flash (Read/Write)

     4096K bytes of processor board Boot flash (Read/Write)

Configuration register is 0x2102


Router>

!--- The router was just powercycled and during bootup a
!---break sequence was sent to the router.


!

     monitor: command "cisco2-C4500" aborted due to user interrupt

     >
     
     >confreg 0x2142


     You must reset or power cycle for new config to take effect


     >reset

System Bootstrap, Version 5.2(7b) [mkamson 7b], RELEASE SOFTWARE (fc1)

     Copyright (c) 1995 by cisco Systems, Inc.

     C4500 processor with 32768 Kbytes of main memory

Self decompressing the image : ##################################

#######################################################

#################################      [OK]

     program load complete, entrypt: 0x80008000, size: 0x6a6b30

     Self decompressing the image : ################################

#################################### [OK]

 Restricted Rights Legend

.......

<snip>

......

     --- System Configuration Dialog ---

Would you like to enter the initial configuration dialog?[yes/no]:n

Press RETURN to get started!


     00:00:05: %LINK-3-UPDOWN: Interface Serial0, changed state to down

     00:00:05: %LINK-3-UPDOWN: Interface Serial1, changed state to down

    .......

     <snip>

    ......

     00:01:29: %LINK-5-CHANGED: Interface Ethernet5, changed state to 
       administratively down

     00:01:29: %LINK-5-CHANGED: Interface Serial0, changed state to 
       administratively down

     Router>

     Router>enable
     Router#copy startup-config running-config
     Destination filename [running-config]?

     1012 bytes copied in 0.276 secs (3667 bytes/sec) 

     Router#show running-config
     Building configuration...
     Current configuration : 1084 bytes
          !
          version 12.2
          service timestamps debug uptime
          service timestamps log uptime
          no service password-encryption
          !
          hostname Router
          !
          enable secret 5 $1$uQ7K$rfZtMRsWsFagqsW4/9K0b1
     
     !--- Since the password is encrypted, we need to replace 
     !--- the password with the new one.


     !
     ip subnet-zero
     !
     !
     !
     !
     interface Ethernet0
     ip address 10.10.10.1 255.0.0.0
     media-type 10BaseT
     !
     interface Ethernet1
     no ip address
     shutdown
     media-type 10BaseT
     !
     Ouput Omitted
     !
     interface Serial0
     ip address 172.16.1.1 255.255.0.0
     !
     Ouput Omitted
     !
     ip classless
     no ip http server
     ip pim bidir-enable
     !
     !
     line con 0
     line aux 0
     line vty 0 4
     login
     !
     end

Router#configure terminal

     Enter configuration commands, one per line. End with CNTL/Z.

     Router(config)#enable secret < password > [Choose a strong password with at least one capital letter, one number, and one special character.]

     Router(config)#^Z 

     00:05:23: %SYS-5-CONFIG_I: Configured from console by console

     Router#show ip interface brief

     Interface IP-Address OK? Method Status Protocol

     Ethernet0 10.10.10.1 YES TFTP administratively down down

Ethernet1 unassigned YES TFTP administratively down down

Ethernet2 unassigned YES TFTP administratively down down

Ethernet3 unassigned YES TFTP administratively down down

Ethernet4 unassigned YES TFTP administratively down down

Ethernet5 unassigned YES TFTP administratively down down

Serial0 unassigned YES TFTP administratively down down

.......

<snip>

......

Serial7 unassigned YES TFTP administratively down down

     Router#

     Router#configure terminal

     Enter configuration commands, one per line. End with CNTL/Z. 

     Router(config)#interface ethernet 0 

     Router(config-if)#no shutdown

     Router(config-if)#

     00:08:06: %LINK-3-UPDOWN: Interface Ethernet0, changed state to up 

     Router(config-if)#^Z

     Router#

     00:09:21: %SYS-5-CONFIG_I: Configured from console by console

     Router#

     Router# 

     Router#copy running-config startup-config

     Destination filename [startup-config]?

     Building configuration...

     [OK]

Router#show version
Cisco Internetwork Operating System Software
IOS (tm) 4500 Software (C4500-IS-M), Version 12.2(10b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 11-Jul-02 17:29 by pwade
Image text-base: 0x60008948, data-base: 0x60C74000



ROM: System Bootstrap, Version 5.2(7b) [mkamson 7b], RELEASE SOFTWARE (fc1)

BOOTLDR: 4500 Software (C4500-BOOT-M), Version 11.3(10), RELEASE SOFTWARE(fc1)
Router uptime is 10 minutes

.......

<snip>

......


     8192K bytes of processor board System flash (Read/Write)

     4096K bytes of processor board Boot flash (Read/Write)

Configuration register is 0x2142

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#config-register 0x2102
Router(config)#^Z
Router#show version
Cisco Internetwork Operating System Software
IOS (tm) 4500 Software (C4500-IS-M), Version 12.2(10b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 11-Jul-02 17:29 by pwade
Image text-base: 0x60008948, data-base: 0x60C74000



ROM: System Bootstrap, Version 5.2(7b) [mkamson 7b], RELEASE SOFTWARE (fc1)

BOOTLDR: 4500 Software (C4500-BOOT-M), Version 11.3(10), RELEASE SOFTWARE (fc1)
     
     Router uptime is 11 minutes

.......

<snip>

......

     00:11:02: %SYS-5-CONFIG_I: Configured from console 4096K bytes of processor board 
       Boot flash (Read/Write)

Configuration register is 0x2142 (will be 0x2102 at next reload)

Related Information

Updated: Apr 10, 2006

Document ID: 24000

Cisco Catalyst 8500 Series Multiservice Switch Routers