Corporate Headquarters

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Obtaining Additional Publications and Information
•
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questions, suggestions, and information about networking products and technologies with Cisco 
experts and other networking professionals. Join a discussion at this URL:
http://www.cisco.com/discuss/networking
•
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C H A P T E R
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Using Cisco IOS Software
This chapter provides helpful tips for understanding and configuring Cisco IOS software using the 
command-line interface (CLI) and includes the following sections:
•
Conventions, page 1-1
•
Understanding Command Modes, page 1-5
•
Using the no and default Forms of Commands, page 1-7
•
Saving Configuration Changes, page 1-8
For an overview of Cisco IOS software configuration, refer to the 
Configuration Fundamentals 
Configuration Guide
. See 
“Related Documentation” section on page xi
for additional information.
Conventions
Command descriptions use the following conventions:
Convention
Description
boldface
font
Commands and keywords are in 
boldface
.
italic
font
Arguments for which you supply values are in 
italics
.
[ ]
Elements in square brackets are optional.
{
x
| 
y
| 
z
}
Alternative keywords are grouped in braces and separated 
by vertical bars.
[
x
| 
y
| 
z
]
Optional alternative keywords are grouped in brackets and 
separated by vertical bars.
string
A nonquoted set of characters. Do not use quotation marks 
around the string or the string will include the quotation 
marks.
screen
font
Terminal sessions and information the system displays are 
in 
screen
font.