Anyone can share your idea of the best way to do this? If a domain which has public and private IP, how the AD server and DNS should be set up? In the old way (before AD time) you can have multi NICs which one is used for Internet, the other one for internal network (private network). But since the introduction of AD which relies so much on DNS, multi NIC becomes tricky. In one server, you have 2 IPs, 1public and 1 private)for the same hostname of the server so the DNS won't work that way. The other way to do this is split-brain DNS which use single NIC on server and make them all as private network on the internal DNS. For the public IP, you can use forward traffic from the router. However when running Exchange on this kind of server, it's becoming tricky because your email header come to other server as "mail.yourEXserver.com 192.168.x.x ". This header creates problem, some anti-spam gateway blocks it because the headerlooks suspicious. so is there a way to do multihome exchange server which can avoid the AD & DNS headache? HN

Hi, Don't multihome the exchange server. Install the exchange server on the private IP segment, use the internal DNS server for name resolution and publish theExchange server in your firewall. Leif

Leif, That's what I thought andis doing but the problem is: my message to China's vendor got blocked. I think because in the header it show the private IP# (though the public IP is there too) Most of the ISP or email provider in China are using "35 antispam" package which highly toued as "Chinese product and technology" (yeah..maybe stole the code from Symantec . Maybe that is the problem. My emails got reject without notifying sopeople don't even know if your message reach your receipient. That sucks. I tried to contact their admin and nobody answers. so much for Chinese product. I don't have trouble sending email to anybody else but to all of those China companies, too bad that what we all are doing. HN