Configuration of a Router as a DHCP Server.

Objectives

Upon the completion of this project, you will be able to configure a router as a dhcp server;

• Design the topology and provide the network devices needed
• Configure and assign address to the Router inteface
• Enable a Router as a DHCP Server
• Assign the IP addresses to the PCs automatically using DHCP
• Test connectivity between devices

Prior Knowledge

Prior to this project, you have learned the basics of computer networking specifically dynamic host configuration protocol and the configurations of networking devices.

• This project focuses specifically on the configuration of a dhcp service on a router that does not have dhcp preconfigured service.

• The project uses the Cisco Packet Tracer to show virtual configurations of the dhcp service on the router.

Instructions

Step 1: Design the topology and provide the network devices needed

a. Select any of the routers from the bottom toolbar , Routers in Network Devices. Choose the 2911 Router from the cisco packet tracer options.

b. Select a switch. Choose 2960 switch option.

c. Select three PCs from End Devices tab, to test connectivity after configuration of the router

d. Connect the devices using the network devices. Use the lightening-bolt tool from the Connections to automatically connect devices using the appropriate cables.

Step 2: Configure and Assign IP Address to the Router Interface

Hover the cursor on the cable connected to the router to reveal the interface. From my project, the interface is Gig0/0. We will assign it the ip address of 192.168.20.1 and a subnet mask of 255.255.255.0. Enter the following commands in the global configuration mode of the CLI tab of the Router configuration window;

Router>enable
Router#configure terminal
Router(config)#interface g0/0
Router(config-if)#ip address 192.168.20.1 255.255.255.0
Router(config-if)#no shutdown
Router(config-if)#exit

Step 3: Enable DHCP service on the Router.

First, you enable the service and then name the dhcp pool. We will name the dhcp pool as ADMIN-DEPT and assign it a network of 192.168.20.0 with a default gateway of 192.168.20.1 which is the ip address of the router.

Router(config)#service dhcp
Router(config)#ip dhcp pool ADMIN-DEPT
Router(dhcp-config)#network 192.168.20.0 255.255.255.0
Router(dhcp-config)#default-router 192.168.20.1
Router(dhcp-config)#dns-server 192.168.20.1
Router(dhcp-config)#exit

The dns server address 192.168.20.1(not particularly correct), is used to show that the dns server should be configured too.

Step 4(Optional): Exclude Specific IP Addresses from the DHCP service.

You will like to exclude certain IP addresses, so as to assign them statically to particular devices of choice or importance such as the printer.

Router(config)#ip dhcp excluded-address 192.168.20.1 192.168.20.10

Step 5: Save the configurations.

Router(config)#do write

Step 6: Assign IP Addresses to the PCs

a. Click open the configuration window of each PCs(PC1, PC2, PC3) one after the other and select the IP Configuration from the Desktop tab.
b. Switch from Static to DHCP by clicking on the DHCP option. This automatically assigns IP addresses to these devices from the DHCP Server, which is the Router.

Notice the “DHCP request is successful” information

Observe and note the IP addresses of the PCs and note also that the addresses are not part of the onces excluded from the dhcp service pool.

Step 7: Test Connectivity between PCs

Select anyone of the PCs to ping the others for connectivity.

a. Click PC3 to open the configuration window, select the Command Prompt from the Desktop tab to open the command line interface

b. Ping PC2 using its IP address.

The ping should be successful, else check the DHCP service configuration on the Router

c. Try pinging PC1 from PC3 or using PC1 or PC2 to ping the other PCs or even Router using the IP address assigned to it which is also the default gateway of the PCs.

Click the Router as DHCP Server to download the packet tracer file and to view the project.