IP addresses with 2 NICs 1

[boardwalk2]

We have a Windows 2003 server with 2 NICs. The first one is setup for internal access behind firewall/rotuer with IP address 192.168.1.x with gateway 192.168.1.1. This IP is reachable from inside the network.

The second NIC is setup for access from outside with a static IP address 71.251.x.y, with subnet 255.255.255.0 and gateway 71.251.x.1 (given to us by ISP). For some reason, this IP is not reachable from outside. It is reachable from inside the network (responds to ping). We know it is a working IP - it is reachable if the another standalone computer is given this static IP, subnet and gateway and connected directly.

Windows 2003 server does give a warning about 2 different gateways when the second NIC is configured to be in a different segment.

How would one configure the 2nd NIC to support 2 isolated segments?

 

[brianinms]

A windows server can only have 1 default gateway.

 

[cajuntank]

Why oh why do you need a directly public accessible NIC on your server?
You already said that the first NIC was behind a firewall/router.

 

[boardwalk2]

The 2nd NIC is setup with an specific IP address and a registered subdomain associated (e.g., smtp.companyA.com) for outgoing/incoming SMTP email. Since some of the major SMTP servers need reverse IP lookup, we need to make the 2nd NICs IP known to outside world, restricting all email traffic to that IP. I understand it is possible to setup the firewall/router with NAT to port forward SMTP to first NIC, but then the same IP is used for both SMTP and all other access.

 

[burtsbees]

Not if you have a separate server for email---a static NAT translation will ensure that mail will go to only that server, if the static NAT is associated with port 25 (or whatever you use---you can specify that). Though it uses the same IP from the outside, only mail will go to the mail server, and only, say web traffic, will go to the web server, specified by static NAT and port 80. All regular internet traffic can use yet the same public IP through PAT (port address translation), or One-To-Many NAT.

Burt