Newer Cisco router and switch can act as Dynamic Host Configuration Protocol (DHCP) server.
This article shows how to configure DHCP server and create appropriate address pool for the clients.

Configuration Steps

  1. Create DHCP pool
  2. Select address pool for client
  3. Configure the basic required parameters
  4. (Optional) Select the address you wish to exclude from the pool

Configutation

We will create DHCP pool with all the necessary configurations

Router(config)#ip dhcp pool INTERNAL_ADDRSS
Router(dhcp-config)#network 192.168.1.0 /24
Router(dhcp-config)#domain-name myoffice.com
Router(dhcp-config)#dns-server 192.168.1.2
Router(dhcp-config)#default-router 192.168.1.1

In the above example we have created an address pool of 192.168.1.0/24 subnet, assigned domain name, dns server and default router (default gateway)
Make sure the default gateway IP address is in the same subnet as the client.

DHCP Server assumes that all IP addresses in a “pool” is available to DHCP clients. Use the following command in global config mode to exclude addresses from the pool.

Router(config)#ip dhcp excluded-address 192.168.1.1 192.168.1.10
Router(config)#

The above command will reserve addresses from 192.168.1.1 to 192.168.1.10

Conclusion

In this tutorial we covered basic configuration for DHCP server.
There are many other advanced options available. For further details check Cisco documentation Configuring the Cisco IOS DHCP Server for further details.