"i tried to put a pic for the network structure but i cannot"
Can not even post a picture on a forum, and your trying to setup a virtual AD domain controller? Maybe you should work basic skills like taking screenshots and posting them first heheheheh
Clearos as gateway - Ok, your this guy http://www.neowin.ne...ros-as-gateway/
I really didn't catch that it was virtual in your first thread. Now that I reread I do see "vms" interface. And lab?. You need to be clear on the details if you want valid help.
How many interfaces does your VM host have? In your other thread you mention vm warkstation.. Now its hyperV? Is this what your trying to stetup? Something like this?
This is how you you normally would setup a Virtual setup where you have a firewall/Router between the physical world and the virtual world.. You really need to draw out your network so we can tell you what your doing wrong. Normally that pnic that is connected to what we can call the wan for your virtual and other physical machines behind your clearos firewall/router doesn't even need to be bound to the OS running on the host. Just needs to be connected to the virtual switching that ties your physical "wan" to your virtual "wan" Now you would assume the host would have an IP on the lan network and bound to the host OS on the same network that the virtual "lan" is.
Please draw out your network how you picture it in your head, and we can help you make that happen. Even if you just use some crayons and scan it. Or here check out http://www.gliffy.com/ free way to do network diagrams.