DHCP Server on Cisco 3750 with VLAN scope

[francis fox]

Hello, I have a Cisco 3750 with several servers connected locally, all on the same VLAN. The 3750 is connected to a wider network with various other servcies including other DHCP servers running. I would like the 3750 to act as the DHCP server for all the devices in the VLAN, but only for that VLAN. Is it possible to restrict the scope of the DHCP address allocation to that VLAN only. We have other DHCP servers running elsewhere in the network and I would like to try and avoid DHCP confusion.

[Pranay Prasoon]

Typically a VLAN is a logical representation of a network. Say if you have vlan 192 representing network 192.168.1.0/24, in that case you can easily define network pool restricted to 192

config t

ip dhcp-exclude address 192.168.1.1

ip dhcp pool 192

   network 192.168.1.0 255.255.255.0

    default-router 192.168.1.1

//With above command switch will only be dhcp server for vlan 192 machines

[Georg Pauwen]

Hello,

once you configure something like the example below, make sure none of your other DHCP servers give out addresses from the same range:

ip dhcp excluded-address 192.168.10.1
!
ip dhcp pool Vlan10
 network 192.168.10.0 255.255.255.0
 domain-name yourdomain.com
 dns-server 8.8.8.8 8.8.8.4
 default-router 192.168.10.1
 lease 3

interface FastEthernet0/0
 switchport access vlan 10