Multiple DHCP Scopes for Vlans
Posted on 2011-02-22
Forgive my ignorance on this subject, but here goes.
DHCP Server: Server 2003 SP2
Switches: Cisco 3560's
We have a vlan setup for our voip phones, and currently they get all of their DHCP from the phone server itself since that vlan could not see our DHCP server. However now I have activated the 2nd nic on our DHCP box, and would like to manage DHCP from there. So I have a nic in the box set to 192.168.0.x and one to 192.168.2.x (and the switch set so the 2.x net only sees that vlan). I know how to add a new scope, but how do I link that scope to a specific nic. Here is how I think it works.
PC/PHONE/WHATEVER needs an IP address, so it asks hey is there a dhcp server here. In which case regardless of subnet this server will respond yes and give it an address.
I found this basic definition.
A DHCP scope is a valid range of IP addresses which are available for assignments or lease to client computers on a particular subnet.
That sounds all good, except the client machine is not on a subnet until the DHCP server assigns one right? So how does it know which scope to use?