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Chapter 9      Troubleshooting
Managing the Cisco Router Web Setup Tool
NoteTo return to the configuration being used before you recovered the lost 
enable password, do not save the configuration changes before rebooting 
the router.
Step 4Reboot the router, and enter the recovered password.
Managing the Cisco Router Web Setup Tool 
The Cisco Router Web Setup tool is a free software configuration utility, 
supporting the Cisco 800 series DSL routers, the Cisco 806 and 831 dual Ethernet 
routers, and the Cisco SOHO series routers. It includes a Web-based GUI that 
offers the following features:
Simplified setup
Advanced configuration
Router security
Router monitoring
Pointers to CRWS Documentation
To find the CRWS Introduction, go to:
http://www.cisco.com/go/CRWS
To see the CRWS User’s Guide, go to:
http://www.cisco.com/univercd/cc/td/doc/clckstrt/crws/ugcrws 30.htm.
To see the CRWS Troubleshooting Guide, go to:
http://www.cisco.com/univercd/cc/td/doc/clckstrt/crws/tgcrws 31.htm. 
						

							 
Chapter 9      Troubleshooting
Managing the Cisco Router Web Setup Tool
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APPENDIXA
Cisco IOS Basic Skills
Understanding how to use Cisco IOS software saves time when you are 
configuring your router. If you need a refresher, take a few minutes to read this 
chapter. If you are already familiar with Cisco IOS software, see Chapter 7, 
“Router Feature Configuration,” and Chapter 8, “Advanced Router 
Configuration.”
This chapter describes what you need to know before you begin configuring your 
Cisco 800 series routers with Cisco IOS software (the software that runs your 
router).
This chapter contains the following sections:
Configuring the Router from a PC, page A-2
Understanding Command Modes, page A-3
Getting Help, page A-6
Enable Secret and Enable Passwords, page A-7
Entering Global Configuration Mode, page A-8
Using Commands, page A-9
Saving Configuration Changes, page A-10 
						

							 
Appendix A      Cisco IOS Basic Skills
Configuring the Router from a PC
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Configuring the Router from a PC
You can configure your router from a connected PC. For information on how to 
connect the PC, refer to the Cisco 826 Routers Hardware Installation Guide. 
After connecting the PC, you need terminal emulation software. The PC uses this 
software to send commands to your router. Ta b l e A - 1 lists some common types 
of this software, which are based on the type of PC you are using.
You can use the terminal emulation software to change settings for the type of 
device that is connected to the PC, in this case a router. Configure the software to 
the following standard VT-100 emulation settings so that your PC can 
communicate with your router:
9600 baud
8 data bits
No parity
1 stop bit
No flow control
These settings should match the default settings of your router. To change the 
router baud, data bits, parity, or stop bits settings, you must reconfigure 
parameters in the ROM monitor. For more information, refer to Appendix B, 
“ROM Monitor.” To change the router flow control setting, use the flowcontrol 
line configuration command.
For information on how to enter global configuration mode so that you can 
configure your router, see the “Entering Global Configuration Mode” section on 
page A-8.
Table A-1 Terminal Emulation Software
PC Operating System Software
Windows 95, Windows 98, 
Windows NT, Windows XPHyperTerm (included with Windows 
software), ProComm Plus
Windows 3.1  Terminal 
(included with Windows software) 
Macintosh ProComm, VersaTerm 
(supplied separately)  
						

							 
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Appendix A      Cisco IOS Basic Skills
Understanding Command Modes
Understanding Command Modes
This section describes the Cisco IOS command mode structure. Each command 
mode supports specific Cisco IOS commands. For example, you can use the 
interface type number command only from global configuration mode.
The following Cisco IOS command modes are hierarchical. When you begin a 
router session, you are in user EXEC mode.
User EXEC
Privileged EXEC
Global configuration
Ta b l e A - 2 lists the command modes that are used in this guide, how to access each 
mode, the prompt you see in that mode, and how to exit to a mode or enter the 
next mode. Because each mode configures different router elements, you might 
need to enter and exit modes frequently. You can see a list of available commands 
for a particular mode by entering a question mark (?) at the prompt. For a 
description of each command, including syntax, refer to the Cisco IOS 12.0 
documentation set. 
						

							 
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Understanding Command Modes
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Table A-2 Command Modes Summary
Mode Access Method PromptExit/Entrance 
Method About this Mode
User EXEC Begin a session with 
your router.
Router>To exit router 
session, enter the 
logout command. Use this mode to:
Change terminal 
settings.
Perform basic tests.
Display system 
information.
Privileged 
EXECEnter the enable 
command from user 
EXEC mode.
Router#To exit to user 
EXEC mode, enter 
the disable 
command.
To enter global 
configuration 
mode, enter the 
configure 
command.Use this mode to:
Configure your 
router operating 
parameters. 
Perform the 
verification steps 
shown in this guide.
To  p r e v e n t  
unauthorized 
changes to your 
router 
configuration, 
access to this mode 
should be protected 
with a password as 
described in 
“Enable Secret and 
Enable Passwords” 
later in this chapter. 
						

							 
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Appendix A      Cisco IOS Basic Skills
Understanding Command Modes
Global 
configurationEnter the configure 
command from 
privileged EXEC 
mode.Router 
(config)#To exit to 
privileged EXEC 
mode, enter the exit 
or end command, 
or press Ctrl-Z.
To enter interface 
configuration 
mode, enter the 
interface 
command.Use this mode to 
configure parameters 
that apply to your router 
as a whole.
Also, you can access the 
following modes, which 
are described later in 
this table:
Interface 
configuration
Router 
configuration
Line configuration
Interface 
configurationEnter the interface 
command (with a 
specific interface, 
such as interface 
ethernet 0) from 
global configuration 
mode.
Router 
(config-if)#To exit to global 
configuration 
mode, enter the exit 
command.
To exit to 
privileged EXEC 
mode, enter the end 
command, or press 
Ctrl-Z. 
To  e n t e r  
subinterface 
configuration 
mode, specify a 
subinterface with 
the interface 
command.Use this mode to 
configure parameters 
for the router Ethernet 
and serial interfaces or 
subinterfaces.
Table A-2 Command Modes Summary (continued)
Mode Access Method PromptExit/Entrance 
Method About this Mode 
						

							 
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Getting Help
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Getting Help
You can use the question mark (?) and arrow keys to help you enter commands.
For a list of available commands at that command mode, enter a question mark:
router> ?
access-enableCreate a temporary access-list entry
access-profileApply user-profile to interface
clearReset functions
...
To complete a command, enter a few known characters followed by a question 
mark (with no space):
router> s?
* s=show set show slip systat
Router 
configurationEnter your router 
command followed 
by the appropriate 
keyword, for example 
router rip, from 
global configuration 
mode.Router 
(config- 
router)#To exit to global 
configuration 
mode, enter the exit 
command.
To exit to 
privileged EXEC 
mode, enter the end 
command, or press 
Ctrl-Z. Use this mode to 
configure an IP routing 
protocol.
Line 
configurationSpecify the line 
command with the 
desired keyword, for 
example, line 0, from 
global configuration 
mode.
Router 
(config- 
line)#To exit to global 
configuration 
mode, enter the exit 
command.
To enter privileged 
EXEC mode, enter 
the end command, 
or press Ctrl-Z.Use this mode to 
configure parameters 
for the terminal line.
Table A-2 Command Modes Summary (continued)
Mode Access Method PromptExit/Entrance 
Method About this Mode 
						

							 
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Appendix A      Cisco IOS Basic Skills
Enable Secret and Enable Passwords
For a list of command variables, enter the show command followed by a space 
and a question mark:
router> show ?
clock Display the system clock
dialerDialer parameters and statistics
exceptionexception information
...
To redisplay a command you previously entered, press the up-arrow key. You can 
continue to press the up arrow key for more commands.
Enable Secret and Enable Passwords
By default, the router ships without password protection. Because many 
privileged EXEC commands are used to set operating parameters, you should 
password-protect these commands to prevent unauthorized use. 
You can use two commands to do this:
enable secret password (a very secure, encrypted password)
enable password (a less secure, unencrypted password)
You must enter an enable secret password to gain access to privileged EXEC 
mode commands.
For maximum security, the passwords should be different. If you enter the same 
password for both during the setup process, your router accepts the passwords, but 
warns you that they should be different. 
An enable secret password can contain from 1 to 25 uppercase and lowercase 
alphanumeric characters. An enable password can contain any number of 
uppercase and lowercase alphanumeric characters. In both cases, a number cannot 
be the first character. Spaces are also valid password characters; for example, two 
words is a valid password. Leading spaces are ignored; trailing spaces are 
recognized.  
						

							 
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Entering Global Configuration Mode
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Entering Global Configuration Mode
To make any configuration changes to your router, you must be in global 
configuration mode. This section describes how to enter global configuration 
mode while using a terminal or PC that is connected to your router console port.
To enter global configuration mode:
Step 1After your router boots up, answer no when the following question displays: 
Would you like to enter the initial configuration dialog [yes]: no
Step 2Enter the enable command:
router> enable
Step 3If you have configured your router with an enable password, enter it when you are 
prompted. 
The enable password does not show on the screen when you enter it. This example 
shows how to enter privileged EXEC mode:
Password: enable_password
router#
Enable mode is indicated by the # in the prompt. You can now make changes to 
your router configuration.
Step 4Enter the configure terminal command to enter global configuration mode, 
indicated by 
(config)# in the prompt: 
router# configure terminal
router (config)#
You can now make changes to your router configuration.