I’m doing a little labwork and wanted to post this really for nothing other than to assist with my remembering it, and hey.. maybe you might find it helpful. Typically whenever I need DHCP I turn to an OS to do that for me, if AD is involved, I’m using Windows, if it’s not I’ll use Linux.  But if you have neither, but do have a Cisco Router, never fear it can do that for you.  Here is our lab, consisting of a single router, a switch, and 3 workstations:

Our IP address range for this lab is 192.168.1.0/24 and we want to reserve ip range 192.168.1.1 – 192.168.1.49 but allow the rest be available for our pool.

My fake PC clients are all set to DHCP.

Step one: Assign an interface on the router for the network.
dhcptest(config)#int fa 0/0
dhcptest(config-if)#description inside
dhcptest(config-if)#ip address 192.168.1.1 255.255.255.0
dhcptest(config-if)#no shut

Step two: Reserve your IP’s that you wish to exclude from your pool.

dhcptest(config)#ip dhcp excluded-address 192.168.1.1 192.168.1.49

Step three: Create your pool, in our test we are naming our pool “inside” but you may name yours whatever you want.

dhcptest(config)#ip dhcp pool inside
dhcptest(dhcp-config)# network 192.168.1.0 255.255.255.0
dhcptest(dhcp-config)#default-router 192.168.1.1
dhcptest(dhcp-config)#dns-server 8.8.8.8 8.8.4.4

Step four: check your dhcp binding

dhcptest#sho ip dhcp binding
IP address Client-ID/ Lease expiration Type
Hardware address
192.168.1.50 0060.7098.9145 -- Automatic
192.168.1.51 00D0.BCA1.3A33 -- Automatic
192.168.1.52 0060.2F5A.3953 -- Automatic
192.168.1.53 000A.4143.6916 -- Automatic

Enjoy!
Here is a link to Cisco’s Guide on DHCP, with cooler options than mine..
Cisco DHCP

Note, I used packet tracer, and in my version, I couldn’t set a second DNS server, but the documentation tells me I can set 8.  😀

Here is a Link to the Packet Tracer File I used:

DHCP LAB

Categorised as: Cisco | Geeking Out