I just finished setting up a new server with Windows server 2008R2 configured as a AD/DNS/NAT. The sever has its original NIC and another dual-port NIC added. All PCs are running windows 7. I have joined the domain after creating an OU for all users except directors. When I tried to access the internet I am getting the error:" your computerappear to be properly configured but the device or resource (primary DNS server) is not responding. I 've checked can't locate the error. Here is my configuration: Server: External NIC Static IP and DNSs from ISP 70.... and Internal NICs 192.168s with no Default GW and DNS PCs: IPs 192.168s range with DNS= server IP What am I doing wrong? Deo MCP MD

Sounds like you're multi-homing your AD/DNS server which will be no end to problems. Disable all but one NIC on DNS server (do not connect it to internet) Make sure local DNS server has own address as primary and 127.0.0.1 as secondary (assuming only one DNS server) in network connection properties and is not multi-homed. Also put public DNS addresses as forwarders only on local DNS server. Client should have local DNS address ONLY so client can find and logon to domain. Forwarders are so clients can find and resolve internet queries. Regards, Dave Patrick .... Microsoft Certified Professional Microsoft MVP [Windows] Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Hi, Thank you for the post. I agree with Dave, DC used with NAT are not supported configuration: http://blogs.technet.com/b/ad/archive/2009/04/22/dcs-and-network-address-translation.aspx Regards,Nick Gu - MSFT

Thanks Dave for your feedback. Here is what we were trying to accomplish: we purchased a Dell hyper-v server PC in which we will have 3 servers, one DC, an Apps server and another will be exchange server. We started by installing the ADDC and joined PCs to domain but none of the PCs(win 7 prof) was able to access the Internet for some reason that we still not been able to figure out. IF I understood you very well it means that I should not multi-homing ADDC it should be on a single machine with one NIC? Thanks Deo MCP MD

Yes, that's correct. Also never join the host to domain and never use it as a domain controller. If you have hyper-v setup questions you can ask them over here. http://social.technet.microsoft.com/Forums/en-US/winserverhyperv/threads Regards, Dave Patrick .... Microsoft Certified Professional Microsoft MVP [Windows] Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Thank you for your answer Dave. The configuration I had before with Windows server 2003 was as follow: Internal Side 19 PCs(IPs 192.168.1s...) ---> Switch-->Server ADDC /NAT ---> Firewalled Wi-fi router --> ISP modem--> INTERNET It was working fine. Contrary to this article: http://blogs.technet.com/b/ad/archive/2009/04/22/dcs-and-network-address-translation.aspx Upon upgraded to windows server 2008R2 that's when the problem started. Maybe the use of dual nic has the weight of the fail. Regards, Deo Microsoft Certified Professional MD

You're welcome. Always better to use a router/nat appliance rather than burdening a server with that. Regards, Dave Patrick .... Microsoft Certified Professional Microsoft MVP [Windows] Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.