CPT 440 Lab 2
Lab #2, part 1 - Configuring IP
Goal
The goal of this lab is to demonstrate how to configure IP addresses on a Cisco
router.
Materials
At least 2 Cisco routers with IOS
9-pin terminal adapter with console cable
Workstation with a 9-pin serial port
Terminal emulation program
Procedure
Checking your interfaces
Cisco routers have multiple interfaces. These interfaces allow for the attachment
of both LAN and WAN interfaces. The router then routes packets between these
various interfaces.
In order to use these interfaces, the interface must be enabled and then
addressed. The interface naming scheme for Cisco is simple…
media type slot#/port#
The “media type” refers to the serial interface, the Ethernet interface, etc.
With the 2500 series routers we do not need to be concerned with slots, so the
the interface would look like: serial 0, serial 1, Ethernet 0. In other routers
you may see FastEthernet 0/0 for example.
1. Preliminary work
Do the configuration steps from the previous lab. The goal of these labs is to
prepare you to configure a router on your own. Each week new steps will be
added, but you will need to practice the previous steps to help complete the goal.
This includes setting up Hyper Terminal, hostname, passwords and line
configuration.
2. Configuring IP addresses
Now that you have working physical and data-link layers, it is time to configure
your network layer. Since we are using IP as our network layer protocol, we are
going to configure an IP address on the ethernet interface.
Check the end of this lab document for the IP ranges assigned to your
workstation.
Figure out the IP address and mask to use for your ethernet interface. Then
enter configuration mode, select the interface, and execute the 'ip address'
command. An example:
Router#configure terminal
Router(config)#interface Ethernet 0
Router(config-if)#ip address (your ethernet ip here)
Now configure the serial interfaces.
Figure out the IP address and mask to use for your Serial interface. Then enter
configuration mode, select the interface, and execute the 'ip address'
command. An example for 192.168.0.3 follows:
Router#configure terminal
Router(config)#interface Serial 0
Router(config-if)#ip address (your serial0 ip here)
Router(config-if)# dce-terminal-timing enable
Router(config-if)# clockrate 19200
Router(config-if)#no shut
Type end to exit out of configuration mode and check the status of the
interface. It should indicate up/up, and show the correct IP address and mask.
If it shows down/down, check the cabling.
3. Configuring an IP route
Once you have the interfaces configured to send and receive data, you will have
to give the router some instructions on what to do with the data. This means some
form of routing should be configured. We are not far along in the class to cover
routing protocols, so we will stick with a static route. This route will tell the
router to send anything it is not sure of to a specific destination. In the case we
will send the traffic to the core router and assume that it knows what do to with it
from there.
You will need to be in the configuration mode. Once there you will type the
following information. The “x” represents the last octet of the core router
interface that you are connected to.
Router(config)#ip route 0.0.0.0.0.0.0.0 192.168.10.x
This command tells the router that data from “0.0.0.0” (meaning any ip
address) with “0.0.0.0” (any mask) should be sent to the core router. The “x”
that you enter will be the other available ip address from your serial range.
4. Checking your configuration and “pre-troubleshooting”
The follow steps are for initial checking of the configuration to double check your
work. The simple steps will help prevent simple mistakes that can cause your
network problems.
1. First, read the configuration. Enter the below command and then
scroll through the configuration and double check that the commands
you have entered are there and correct. This will also give you
experience with reading configs. The space bar scrolls a page at a time
and the enter key will scroll one line at a time. Pressing “c” will break
the scroll and return you to a command line.
Router#show running-configuration
Note: Other commands such as “write terminal” will still
accomplish the same thing, but it is no longer considered a “valid”
Cisco command.
2. If you want to check the configuration for a specific interface you can
do the following.
Router#show run interface serial 0
Note: “Serial 0” is just an example and the command will work with
any available interface. This includes interface that are not configured
yet.
To check the status of our interfaces do the following command.
Router#show ip interface brief
The interface can be in four states: administratively down,
down/down, up/down, and up/up. Administratively down means the
interface has not been enabled by the router administrator. Down/down
means the router has no working physical connectivity on the
interface. Up/down means the physical connectivity is there, but the
data-link protocols cannot see other devices on the media. Finally,
up/up means that both physical and data-link connectivity are working
on the interface.
Note1: The most common mistake made by students (and sometimes
professionals) is to forget the “no shut” command. This is one of
those simple problems that are often overlooked and cause major
headaches.
Note2: The same information can be seen using the “show
interface (interface type and number)” But the
“brief” command is easier to read for a simple status check. The
longer show command is useful for checking on how many packets are
going in and out of the interface, how much bandwidth is being used,
etc. Go ahead and try the command for you interfaces and look at the
available information.
3. Issue the following command to see the routing information on your
router.
Router#show ip route
This will give you a readout on all the routing information that the
router has learned. This can be gathered through your configuration of
interfaces, dynamic routing protocols or by static routes. This
command is an easy way to verify the router is passing traffic in a way
that you intend.
4. Issue the following command to check your connection to your LAN
via the Ethernet port(s).
Router#show arp
This readout will show the IP addresses and MAC addresses that the
router can see from the Ethernet(s) interface(s). If you have multiple
Ethernet interfaces it will also indicate which interface the devices are
connected to.
Note: The router’s Ethernet IP address will be listed as well. This is
the IP gateway for your LAN. The router borrows the MAC address
form the Ethernet port whenever a MAC is needed for the router.
IP RANGES BY STATION
The core router interface that you connect to will be the first useable IP address in the
block and the edge router that you are configuring will use the second useable IP address
in the range.
You can select any IP address in the Ethernet range for your gateway (Ethernet interface
IP address), but most people will use the first available or the last.
Station 1
Serial Range:
192.168.10.80/30
Ethernet Range:
1.0.0.0/8
Station 2
Serial Range:
Ethernet Range:
192.168.10.4/30
2.0.0.0/8
Station 3
Serial Range:
Ethernet Range:
192.168.10.8/30
3.0.0.0/8
Station 4
Serial Range:
Ethernet Range:
192.168.10.12/30
4.0.0.0/8
Station 5
Serial Range:
Ethernet Range:
192.168.10.16/30
5.0.0.0/8
Station 6
Serial Range:
Ethernet Range:
192.168.10.20/30
6.0.0.0/8
Station 7
Serial Range:
Ethernet Range:
192.168.10.24/30
7.0.0.0/8
Station 8
Serial Range:
Ethernet Range:
192.168.10.28/30
8.0.0.0/8
Station 9
Serial Range:
Ethernet Range:
192.168.10.32/30
9.0.0.0/8
Station 10
Serial Range:
Ethernet Range:
192.168.10.36/30
10.0.0.0/8
Station 11
Serial Range:
Ethernet Range:
192.168.10.40/30
11.0.0.0/8
Station 12
Serial Range:
Ethernet Range:
192.168.10.44/30
12.0.0.0/8
Station 13
Serial Range:
Ethernet Range:
192.168.10.48/30
13.0.0.0/8
Station 14
Serial Range:
Ethernet Range:
192.168.10.52/30
14.0.0.0/8
Station 15
Serial Range:
Ethernet Range:
192.168.10.56/30
15.0.0.0/8
Station 16
Serial Range:
Ethernet Range:
192.168.10.60/30
16.0.0.0/8
Station 17
Serial Range:
Ethernet Range:
192.168.10.64/30
17.0.0.0/8
Station 18
Serial Range:
Ethernet Range:
192.168.10.68/30
18.0.0.0/8
Station 19
Serial Range:
Ethernet Range:
192.168.10.72/30
19.0.0.0/8
Station 20
Serial Range:
Ethernet Range:
192.168.10.76/30
20.0.0.0/8