When a router is shipped from Cisco, the configuration is default.  These preconfigured settings may conflict your existing network configuration and setup. Though settings in Cisco router  devices can be made through SDM (Security Device Manager ), it always needs a CLI (Command Line Interface) to be enabled.

This Cisco CCNA Tutorial and Packet Tracer Practice Exam is basic and requires no computation to use.  This can be applied into real Cisco router device but if you are a beginner, I would recommend you download an application like Packet Tracer, GNS3 or the like for practice.

For students and beginners, I would recommend you read some of the basics in Cisco CCNA Tutorials and Practice Exams.

For this example, I use Packet Tracer Version 5.3.1.0044. You may download the application in Cisco Website.

Cisco CCNA Video Tutorial: Manually Assign IP Address to Router’s Lan Interface

Download Packet Tracer Exercise: CCNA Tutorial and Practice Exam #1

There are several steps to perform for Cisco Router Lan Interface Configuration

Step 1:  Assign a Hostname to Your Router

Though it is not necessary to perform this step, it is a good practice that your Cisco router is configured with hostname. This is handy when dealing with multiple routers in real application.

First, log in to privileged EXEC mode by entering enable command, then enter the configuration mode using the configure terminal (config t as a short command), type in hostname to assign a hostname to your Cisco router.  In this exercise, we will assign our first router as “Lab-R1“.

Step 2: Configure Lan Interface in Interface Configuration Mode

You must be in the interface configuration mode to configure the lan interface. From the global configuration mode, enter interface fastethernet0/0  (shortened as int fa0/0) where fastethernet is the interface and 0/0 is the interface number.

You can easily identify that you’re in the interface configuration mode by looking at the prompt as it changed from config to config-if.

Step 3: Provide a Description for Lan Interface

You may or may not provide a description for the lan interface. However, it is a good practice that description is added to your routers lan interface. You can do this by using the command description (shortened as descr). The command description should be entered in the interface configuration mode.

Step 4: Specify an Ip Address to the Lan Interface

There are different classes of ip address that can be selected and applied in the Cisco routers interface. We will be using the Class C Ip Address, 192.168.0.1 with a subnet mask of 255.255.255.0. Use the command ip address (shortened as ip addr) <ip address> <subnet mask>.

In this example, ip address 192.168.0.1 255.255.255.0 which is the private address of class C. Private addresses are specific range of ip addresses that are intended to be used on Local Area Networks.

Step 5: Turn On the Lan Interface for Use

The Lan interface is shutdown by default. To use it, simply execute the command no shutdown (shortened as no shut). Message will appear on the prompt indicating that that interface has been turned on.

In some cases that you want to turn off the interface, simply go to the interface configuration mode and execute the command shutdown. The interface will be set to administratively down.

Step 6: Check the Interface Configuration

To check the configuration, you must be at the privileged EXEC mode. Enter the end command to exit. Execute show running-config (sh run) to display the running configuration of the router. You may also use show ip interface brief (sh ip int br) to display a brief summary of router interface.

Step 7: Save the Lan Interface Configuration

To save, at the privileged EXEC mode, execute the command copy running-config startup-config which means copy the current settings and save to routers memory.

You can download the Packet Tracer Exercise #1 and see if you can configure Lan Interface Fa1/0 with ip address 10.0.0.1 subnet mask 255.0.0.0

Download: CCNA Tutorial and Practice Exam #1

Summary: How to configure the routers Lan Interface

Router>enable

Router#  config t

Router(config)# hostname Lab-R1

Lab-R1(config)# int fa0/0

Lab-R1(config)# ip addr 192.168.0.1 255.255.255.0

Lab-R1(config-if)# descr LAN port for Inside Network

Lab-R1(config-if)# no shut

Lab-R1(config-if)# end

Lab-R1#