Domain controller vs Untangle server

[CarlCioffi]

I am having a problem with subnets and domain controllers and the untangle server.

Question: Does my domain controller take precedence over my untangle server?

My untangle server network interface is set for a 255.255.255.0 subnet which my remote network administrator tells me will give me an IP address with that subnet. However, my domain controller has a scope setting with a 255.0.0.0 subnet and after changing the untangle server I still get the 255.0.0.0 subnet. I'm no network administrator but it would seem that I have to modify my domain controller as well even though the remote network administrator says it doesn't matter.

Somebody please enlighten me.

[TirsoJRP]

IP range?
A network diagram would help too.

[CarlCioffi]

I have a network diagram in PDF but it's too big to upload and I don't have the original document. Our internal IP addresses are in the 10.2.6.x range and the external IP addresses I'm trying to get to are in the 10.32.25.x range. Internally our subnet is 255.0.0.0 and the external subnet is 255.255.255.0. Our remote network administrator is microsoft certified network engineer and doesn't have an answer! So much for certifications.

I think I got the image attached.

Maybe not, I haven't had enough posts yet.

[TirsoJRP]

Since you are using 10.2.6.x with a subnet mask 255.0.0.0 your internal network is actually 10.x.x.x which includes the IP's in the remote network.

You have an overlapping problem, the only way to fix this is using an smaller subnet that doesn't overlap with the remote network.

[jcoehoorn]

Your untangle server should match it's internal interface subnet to whatever the dhcp server for your internal network is doing. In this case, that's most likely the Active Directory server. So you should match the active directory subnet.

However, it sounds like your the subnet used by your Active Directory installation is wrong. Since your router is using a non-public routable internal address, it looks like you have things setup to do what is called "double NAT", and that's bad. What you want to do, if possible, is place either your router or the untangle box into bridge mode, and then set up your network to use the same ip range/subnet as the internal interface of your router, so that you only have a single level of NAT.