Switching DHCP hosts

[thejackal85]

Hey hey all, so quick question for the network experts out there. As of now, DHCP is controlled through our firewall (SonicWall) and we are wanting to move it to our domain controller for better control and more options.

Is this as easy as it sounds? Create DHCP networks on the DC, keep them disabled for now. Kill the DHCP server on the firewall, restart all of our systems and they get the new correct lease? My issue is if that is the case, how will the computers distinguish what to get from what VLAN on the firewall? For example, X0 is default network, X1 is DMZ, etc. Will the gateway entries in the DHCP scope setup on the DC provide that?

 

[Pat Flynn]

As long as you have correctly specified your Sonicwall as the 'Gateway' in the DHCP Server configuration on your DC, all traffic routing will be handled by the Sonicwall. The DC will control who get what IP, that's all.
As for the VLANs, where a computer goes is based on what routes are programmed into your Gateway. Routes are basically traffic signs to point where to connect to a network.
Here's an example:
Say you have a computer with an IP of 192.168.1.100. You need to access information on a network device of 192.168.50.150. When 192.168.1.100 tries to communicate with 50.150, the very first step it takes is to talk to the Gateway. If you have a static route programmed to 192.168.50.0/24, then the gateway will direct the traffic to that network (as long as you have the firewall policies to allow it). Note that the Gateway will need a physical or virtual connection to that network in some way to be able to route the traffic there. Even if it has to forward the traffic to another gateway, you'll still need a connection to the other gateway.