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Cisco 3825 Mobile Wireless Edge Router Software Configuration Guide
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Cisco IOS Software Basics
This chapter describes what you need to know about the Cisco IOS software before you configure the
router by using the CLI. This chapter includes the following topics:
• Getting Help, this page
• Understanding Command Modes, page 2-2
• Undoing a Command or Feature, page 2-3
• Saving Configuration Changes, page 2-3
• Where to Go Next, page 2-3
Understanding this information will save you time as you begin to use the CLI. If you have never used
the Cisco IOS software or if you need a refresher, read this chapter before you proceed to Chapter 3,
“First-Time Configuration.”
If you are already familiar with the Cisco IOS software, proceed to Chapter 3, “First-Time
Configuration”.

Getting Help

Use the question mark (?) and arrow keys to help you enter co mmands:
• For a list of available commands, enter a question mark:
Router> ?
• To complete a command, enter a few known characters followed by a question mark (with no space):
Router> s?
• For a list of command variables, enter the command followed by a space and a question mark:
Router> show ?
• To redisplay a command that you previously entered, press the Up Arrow key. Continue to press the
Up Arrow key to see more commands.