Password Recovery Procedure for the Cisco 1700 and 1800 Series

Password Recovery Procedure for the Cisco 1700
and 1800 Series Routers
Document ID: 22187
Contents
Introduction
Prerequisites
Requirements
Components Used
Related Products
Conventions
Step−by−Step Procedure
Example of Password Recovery Procedure
Related Information
Introduction
This document describes how to recover the enable password and the enable secret passwords. These
passwords protect access to privileged EXEC and configuration modes. The enable password password can
be recovered, but the enable secret password is encrypted and must be replaced with a new password. Use the
procedure described in this document in order to replace the enable secret password.
Prerequisites
Requirements
There are no specific requirements for this document.
Components Used
The information in this document is based on these hardware versions:
• Cisco 1700 Series Router
• Cisco 1800 Series Router
The information in this document was created from the devices in a specific lab environment. All of the
devices used in this document started with a cleared (default) configuration. If your network is live, make sure
that you understand the potential impact of any command.
Related Products
Refer to Password Recovery Procedures for information on how to recover passwords for related products.
Conventions
Refer to Cisco Technical Tips Conventions for information on document conventions.
Step−by−Step Procedure
Follow these steps in order to recover your password:
1. Attach a terminal or PC with terminal emulation to the console port of the router.
Use these terminal settings:
♦ 9600 baud rate
♦ No parity
♦ 8 data bits
♦ 1 stop bit
♦ No flow control
Refer to these documents for information on how to cable and connect a terminal to the console port
or the AUX port:
♦ Cabling Guide for Console and AUX Ports
♦ Connecting a Terminal to the Console Port on Catalyst Switches
♦ Connect a Terminal to Catalyst 2948G−L3, 4908G−L3, and 4840G Series Switches
2. If you can access the router, type show version at the prompt, and record the configuration register
setting. See Example of Password Recovery Procedure in order to view the output of a show version
command
Note: The configuration register is usually set to 0x2102 or 0x102. If you can no longer access the
router (because of a lost login or TACACS password), you can safely assume that your configuration
register is set to 0x2102.
3. Use the power switch in order to turn off the router, and then turn the router back on.
Important Notes:
♦ In order to simulate this step on a Cisco 6400, pull out and then plug in the Node Route
Processor (NRP) or Node Switch Processor (NSP) card.
♦ In order to simulate this step on a Cisco 6x00 with NI−2, pull out and then plug in the NI−2
card.
4. Press Break on the terminal keyboard within 60 seconds of power up in order to put the router into
ROMMON.
If the break sequence does not work, refer to Standard Break Key Sequence Combinations During
Password Recovery for other key combinations.
5. Type confreg 0x2142 at the rommon 1> prompt in order to boot from Flash.
This step bypasses the startup configuration where the passwords are stored.
6. Type reset at the rommon 2> prompt.
The router reboots, but ignores the saved configuration.
7. Type no after each setup question, or press Ctrl−C in order to skip the initial setup procedure.
8. Type enable at the Router> prompt.
You are in enable mode and should see the Router# prompt.
9. Type configure memory or copy startup−config running−config in order to copy the nonvolatile
RAM (NVRAM) into memory.
Important: Do not type copy running−config startup−config or write. These commands erase your
startup configuration.
10. Type show running−config.
The show running−config command shows the configuration of the router. In this configuration, the
shutdown command appears under all interfaces, which indicates all interfaces are currently shut
down. In addition, the passwords (enable password, enable secret, vty, console passwords) are in
either an encrypted or unencrypted format. You can reuse unencrypted passwords. You must change
encrypted passwords to a new password.
11. Type configure terminal.
The hostname(config)# prompt appears.
12. Type enable secret <password> in order to change the enable secret password. For example:
hostname(config)#enable secret cisco
13. Issue the no shutdown command on every interface that you use.
If you issue a show ip interface brief command in privilege EXEC mode, every interface that you
want to use should display up up. For example:
Router#show ip interface brief
14. Type config−register <configuration_register_setting>. Where configuration_register_setting is
either the value you recorded in step 2 or 0x2102 . For example:
hostname(config)#config−register 0x2102
15. Press Ctrl−z or end in order to leave the configuration mode.
The hostname# prompt appears.
16. Type write memory or copy running−config startup−config in order to commit the changes.
Example of Password Recovery Procedure
This section provides an example of the password recovery procedure. This example was created with a Cisco
2600 Series Router. Even if you do not use a Cisco 2600 Series Router, this output provides an example of
what you should experience on your product.
Router>enable
Password:
Password:
Password:
% Bad secrets
Router>show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600−IS−M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
Copyright (c) 1986−1999 by cisco Systems, Inc.
Compiled Tue 07−Dec−99 02:21 by phanguye
Image text−base: 0x80008088, data−base: 0x80C524F8
ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
Router uptime is 3 minutes
System returned to ROM by abort at PC 0x802D0B60
System image file is "flash:c2600−is−mz.120−7.T"
cisco 2611 (MPC860) processor (revision 0x202) with 26624K/6144K bytes of memory.
Processor board ID JAB031202NK (3878188963)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
2 Ethernet/IEEE 802.3 interface(s)
2 Serial(sync/async) network interface(s)
1 ISDN Basic Rate interface(s)
32K bytes of non−volatile configuration memory.
8192K bytes of processor board System flash partition 1 (Read/Write)
8192K bytes of processor board System flash partition 2 (Read/Write)
Configuration register is 0x2102
Router>
!−−− The router was just powercycled, and during bootup a
!−−− break sequence was sent to the router.
!
*** System received an abort due to Break Key ***
signal= 0x3, code= 0x500, context= 0x813ac158
PC = 0x802d0b60, Vector = 0x500, SP = 0x80006030
rommon 1 > confreg 0x2142
You must reset or power cycle for new config to take effect
rommon 2 > reset
System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
Copyright (c) 1999 by cisco Systems, Inc.
TAC:Home:SW:IOS:Specials for info
C2600 platform with 32768 Kbytes of main memory
program load complete, entry point: 0x80008000, size: 0x6fdb4c
Self decompressing the image : ###############################
##############################################################
##############################################################
##############################################################
############################### [OK]
Restricted Rights Legend
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software − Restricted
Rights clause at FAR sec. 52.227−19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227−7013.
cisco Systems, Inc.
170 West Tasman Drive
San Jose, California 95134−1706
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600−IS−M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
Copyright (c) 1986−1999 by cisco Systems, Inc.
Compiled Tue 07−Dec−99 02:21 by phanguye
Image text−base: 0x80008088, data−base: 0x80C524F8
cisco 2611 (MPC860) processor (revision 0x202) with 26624K/6144K bytes of memory.
Processor board ID JAB031202NK (3878188963)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
2 Ethernet/IEEE 802.3 interface(s)
2 Serial(sync/async) network interface(s)
1 ISDN Basic Rate interface(s)
32K bytes of non−volatile configuration memory.
8192K bytes of processor board System flash partition 1 (Read/Write)
8192K bytes of processor board System flash partition 2 (Read/Write)
−−− System Configuration Dialog −−−
Would you like to enter the initial configuration dialog? [yes/no]: n
Press RETURN to get started!
00:00:19: %LINK−3−UPDOWN: Interface BRI0/0, changed state to up
00:00:19: %LINK−3−UPDOWN: Interface Ethernet0/0, changed state to up
00:00:19: %LINK−3−UPDOWN: Interface Ethernet0/1, changed state to up
00:00:19: %LINK−3−UPDOWN: Interface Serial0/0, changed state to down
00:00:19: %LINK−3−UPDOWN: Interface Serial0/1, changed state to down
00:00:20: %LINEPROTO−5−UPDOWN: Line protocol on Interface BRI0/0,
changed state to down
00:00:20: %LINEPROTO−5−UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to up
Router>
00:00:20: %LINEPROTO−5−UPDOWN: Line protocol on Interface Ethernet0/1,
changed state to up
00:00:20: %LINEPROTO−5−UPDOWN: Line protocol on Interface Serial0/0,
changed state to down
00:00:20: %LINEPROTO−5−UPDOWN: Line protocol on Interface Serial0/1,
changed state to down
00:00:50: %SYS−5−RESTART: System restarted −−
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600−IS−M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
Copyright (c) 1986−1999 by cisco Systems, Inc.
Compiled Tue 07−Dec−99 02:21 by phanguye
00:00:50: %LINK−5−CHANGED: Interface BRI0/0,
changed state to administratively down
00:00:52: %LINK−5−CHANGED: Interface Ethernet0/0,
changed state to administratively down
00:00:52: %LINK−5−CHANGED: Interface Serial0/0,
changed state to administratively down
00:00:52: %LINK−5−CHANGED: Interface Ethernet0/1,
changed state to administratively down
00:00:52: %LINK−5−CHANGED: Interface Serial0/1,
changed state to administratively down
00:00:53: %LINEPROTO−5−UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to down
00:00:53: %LINEPROTO−5−UPDOWN: Line protocol on Interface Ethernet0/1,
changed state to down
Router>
Router>enable
Router#copy startup−config running−config
Destination filename [running−config]?
1324 bytes copied in 2.35 secs (662 bytes/sec)
Router#
00:01:24: %LINEPROTO−5−UPDOWN: Line protocol on Interface BRI0/0:1,
changed state to down
00:01:24: %LINEPROTO−5−UPDOWN: Line protocol on Interface BRI0/0:2,
changed state to down
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#enable secret < password >
Router(config)#^Z
00:01:54: %SYS−5−CONFIG_I: Configured from console by console
Router#show ip interface brief
Interface
IP−Address
OK? Method
Status
Protocol
Ethernet0/0 10.200.40.37
YES TFTP
administratively down
down
Serial0/0
unassigned
YES TFTP
administratively down
down
BRI0/0
193.251.121.157
YES unset
administratively down
down
BRI0/0:1
unassigned
YES unset
administratively down
down
BRI0/0:2
unassigned
YES unset
administratively down
down
Ethernet0/1 unassigned
YES TFTP
administratively down
down
Serial0/1
unassigned
YES TFTP
administratively down
down
Loopback0
193.251.121.157
YES TFTP
up
up
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#interface Ethernet0/0
Router(config−if)#no shutdown
Router(config−if)#
00:02:14: %LINK−3−UPDOWN: Interface Ethernet0/0, changed state to up
00:02:15: %LINEPROTO−5−UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to up
Router(config−if)#interface BRI0/0
Router(config−if)#no shutdown
Router(config−if)#
00:02:26: %LINK−3−UPDOWN: Interface BRI0/0:1, changed state to down
00:02:26: %LINK−3−UPDOWN: Interface BRI0/0:2, changed state to down
00:02:26: %LINK−3−UPDOWN: Interface BRI0/0, changed state to up
00:02:115964116991: %ISDN−6−LAYER2UP: Layer 2 for Interface BR0/0,
TEI 68 changed to up
Router(config−if)#^Z
Router#
00:02:35: %SYS−5−CONFIG_I: Configured from console by console
Router#copy running−config startup−config
Destination filename [startup−config]?
Building configuration...
[OK]
Router#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600−IS−M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
Copyright (c) 1986−1999 by cisco Systems, Inc.
Compiled Tue 07−Dec−99 02:21 by phanguye
Image text−base: 0x80008088, data−base: 0x80C524F8
ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
Router uptime is 3 minutes
System returned to ROM by abort at PC 0x802D0B60
System image file is "flash:c2600−is−mz.120−7.T"
cisco 2611 (MPC860) processor (revision 0x202)
with 26624K/6144K bytes of memory.
Processor board ID JAB031202NK (3878188963)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
2 Ethernet/IEEE 802.3 interface(s)
2 Serial(sync/async) network interface(s)
1 ISDN Basic Rate interface(s)
32K bytes of non−volatile configuration memory.
8192K bytes of processor board System flash partition 1 (Read/Write)
8192K bytes of processor board System flash partition 2 (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
00:03:20: %SYS−5−CONFIG_I: Configured from console by console
Router#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600−IS−M), Version 12.0(7)T, RELEASE SOFTWARE (fc2)
Copyright (c) 1986−1999 by cisco Systems, Inc.
Compiled Tue 07−Dec−99 02:21 by phanguye
Image text−base: 0x80008088, data−base: 0x80C524F8
ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
Router uptime is 3 minutes
System returned to ROM by abort at PC 0x802D0B60
System image file is "flash:c2600−is−mz.120−7.T"
cisco 2611 (MPC860) processor (revision 0x202)
with 26624K/6144K bytes of memory.
Processor board ID JAB031202NK (3878188963)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
2 Ethernet/IEEE 802.3 interface(s)
2 Serial(sync/async) network interface(s)
1 ISDN Basic Rate interface(s)
32K bytes of non−volatile configuration memory.
8192K bytes of processor board System flash partition 1 (Read/Write)
8192K bytes of processor board System flash partition 2 (Read/Write)
Configuration register is 0x2142 (will be 0x2102 at next reload)
Router#
Related Information
• Password Recovery Procedures
• Cabling Guide for Console and AUX Ports
• Connecting a Terminal to the Console Port on Catalyst Switches
• Connect a Terminal to Catalyst 2948G−L3, 4908G−L3, and 4840G Series Switches
• Standard Break Key Sequence Combinations During Password Recovery
• Technical Support − Cisco Systems
Contacts & Feedback | Help | Site Map
© 2009 − 2010 Cisco Systems, Inc. All rights reserved. Terms & Conditions | Privacy Statement | Cookie Policy | Trademarks of
Cisco Systems, Inc.
Updated: Jan 06, 2009
Document ID: 22187
Open as PDF
Similar pages