I have two Exchange 2000 SP3 servers each running on Windows 2000 Servers with SP4. Server A is configured with both an internal NIC and external (Internet IP) NIC. Server B just has an internal NIC enabled. Server A sends and receives all internal and Internet email. Server B is mainly just for backup purposes in case Server A would fail.
My problem is that Server A's Internet IP address has been blacklisted on DSBL.ORG's web site so we cannot send email to some domains. I've done checks (using Telnet and ORDB) for open relays but they all come back fine. Since this seems to be an extremely slow process to get resolved, I'm looking at some temporary solutions.
One temporary solution, I'm thinking, is to enable the Internet NIC on Server B and somehow configure Server A to send all Internet email through Server B. Unfortunately, I couldn't figure out how to do this if it's even possible. I don't want to change DNS entries as I still want email to come into Server A. I just want Server B to be able to send all Internet email through its SMTP connection. Can you tell me if this is possible and how to do it?
I should also mention that Server A is also my proxy server (running ISA Server 2000) and my Web Site (running IIS 5.0, I think).
If the above won't work or cannot be done, is it possible to add another NIC to Server A, configure it with a different Internet IP address then send all SMTP Internet email throught the new NIC? If so, how can I configure Exchange to look at the second Internet NIC?
I'm assuming here that the blacklist is by IP address and not by domain name. Looking at dnsstuff for my IP address, this appears to be correct.