Layer 3 Switching Software Feature and Configuration Guide, 12.0(10)W5(18c)
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Table of Contents

Before You Begin

Before You Begin

This chapter gives you a process to follow in configuring your switch router, lists the information you need to have available before you begin, and describes Cisco IOS command modes. This chapter includes the following topics:

Suggested Procedure for Configuring Your Switch Router

The following steps represent a suggested procedure for configuring your switch router.

Step 1   Set up the hardware as described in the chassis installation guide for your switch router.

Step 2   Configure the processor module. See "Configuring the Route Processor." For the Catalyst 8540 MSR, refer to the ATM Switch Router Software Configuration Guide .

Step 3   Configure the interfaces. See "Configuring Interfaces."

Step 4   Configure networking and routing protocols. See "Configuring Networking Protocols."

Step 5   Configure bridging. See "Configuring Bridging."

Step 6   Configure the EtherChannel. See "Configuring EtherChannel."

Step 7   Configure optional QoS and SDM functionality. See "Configuring Quality of Service," and "Configuring Switching Database Manager."

Step 8   Perform optional system management and performance tasks.

Preparing to Configure Your Switch Router

Before configuring your switch router, have the following information available:

  • A map of your network topology

  • The network protocol(s) you are supporting (IP, Novell IPX, or AppleTalk)

  • The routing protocol you will use for each network protocol

  • The IP or IPX addresses and the IP subnet masks for each network interface

  • The IP addressing plan for each network protocol

About the Command Line Interface

You can configure the switch router from the command-line interface (CLI) that runs on the router console or terminal, or by using remote access.

To use the CLI, your terminal must be connected to the switch router through the console port or one of the TTY lines. By default, the terminal is configured to a basic configuration, which should work for most terminal sessions.

About Cisco IOS Command Modes

The Cisco IOS user interface is divided into many different modes. The commands available to you depend on which mode you are currently in. To get a list of the commands available in a given mode, type a question mark (?) at the system prompt.

When you start a session on the router, you begin in user mode, often called EXEC mode. Only a limited subset of the commands are available in EXEC mode. To have access to all commands, you must enter privileged EXEC mode. Normally, you must type in a password to access privileged EXEC mode. From privileged mode, you can type in any EXEC command or access global configuration mode. Most of the EXEC commands are one-time commands, such as show commands, which show the current configuration status, and clear commands, which clear counters or interfaces. The EXEC commands are not saved across reboots of the router.

The configuration modes allow you to make changes to the running configuration. If you later save the configuration, these commands are stored across router reboots. You must start at global configuration mode. From global configuration mode, you can enter interface configuration mode, subinterface configuration mode, and a variety of protocol-specific modes.

Read only memory (ROM) monitor mode is a separate mode used when the router cannot boot properly. For example, your router or access server might enter read-only memory (ROM) monitor mode if it does not find a valid system image when it is booting, or if its configuration file is corrupted at startup.

Table 2-1 lists and describes the most commonly used modes, how to enter the modes, and the resulting system prompts. The system prompt helps you identify which mode you are in and, therefore, which commands are available to you.


Table 2-1: Frequently Used IOS Command Modes
Mode Description of Use How to Access Prompt

User EXEC

To connect to remote devices, change terminal settings on a temporary basis, perform basic tests, and display system information.

Log in.

Router>

Privileged EXEC (Enable)

To set operating parameters. The privileged command set includes the commands in user EXEC mode, as well as the configure command. Use this command to access the other command modes.

From the user EXEC mode, enter the enable command and the enable password.

Router#

Global configuration

To configure features that affect the system as a whole.

From the privileged EXEC mode, enter the configure terminal command.

Router(config)#

Interface configuration

To enable features for a particular interface. Interface commands enable or modify the operation of a Gigabit Ethernet or Fast Ethernet port.

From global configuration mode, enter the interface type location command.

For example, enter
interface fastethernet 0/0/1
or
interface gigabitethernet 1/0/0.

Router(config-if)#

Line configuration

To configure the console port or VTY line from the directly connected console or the virtual terminal used with Telnet.

From global configuration mode, enter the line console 0 command to configure the console port, or the line vty line-number command to configure a VTY line.

Router(config-line)#


The Cisco IOS command interpreter, called the EXEC, interprets and executes the commands you enter. You can abbreviate commands and keywords by entering just enough characters to make the command unique from other commands. For example, you can abbreviate the show command to sh and the configure terminal command to config t.

When you type exit, the switch router backs out one level. In general, typing exit returns you to global configuration mode. To exit configuration mode completely and return to privileged EXEC mode, press Ctrl-Z or end.

Listing Cisco IOS Commands and Syntax

In any command mode, you can get a list of available commands by entering a question mark (?).

Router> ?

To obtain a list of commands that begin with a particular character sequence, type in those characters followed immediately by the question mark (?). Do not include a space. This form of help is called word help, because it completes a word for you.

Router# co?

configure

To list keywords or arguments, enter a question mark in place of a keyword or argument. Include a space before the question mark. This form of help is called command syntax help, because it reminds you which keywords or arguments are applicable based on the command, keywords, and arguments you have already entered.

Router# configure ?

	memory               Configure from NV memory
	network              Configure from a TFTP network host
	overwrite-network    Overwrite NV memory from TFTP network host
	terminal             Configure from the terminal

To redisplay a command you previously entered, press the Up-arrow key. You can continue to press the Up-arrow key to see more previously issued commands.

Tip If you are having trouble entering a command, check the system prompt, and enter the question mark (?) for a list of available commands. You might be in the wrong command mode or using incorrect syntax.

You can press Ctrl-Z or end in any mode to immediately return to privileged EXEC (enable) mode, instead of entering exit, which returns you to the previous mode.

More Configuration Documentation

After you have installed the hardware, checked all external connections, turned on the system power, allowed the system to boot up, and minimally configured the system, you might need to perform more complete and complex configurations, which are beyond the scope of this document.

The Cisco IOS software running your switch router contains extensive features and functionality. The effective use of many of these features is easier if you have more reference information. For additional information on Cisco IOS software and configuring your switch router, refer to the following configuration and command reference publications on CCO: