Our Exchange 2003 Server has 2 nic cards in it. Only one is active. The nic card that is active has an IP address that is in our DMZ. So, while all of our other servers on the LAN, that make up the rest of 2003 domain, have an internal IP addressing scheme of 172.16.10.x, the Exchange server is 172.16.30.x and is LAN accessible.
The Exchange server is a single box doing everything - data/information stores/mailboxes/OWA/SMTP gateway. Occasionally we have intermittent connectivity issues, where users will receive the dreaded 'Requesting Data from Exchange Server' message.
I wonder if taking the current nic card and its IP (172.16.30.x) and dedicating it exclusively for SMTP/OWA traffic and taking the other nic and giving it a (172.16.10.x) address and changing the internal DNS reflect the 172.16.10.x address for the Exchange Server's hostname, would give any kind of performance benefit on the local LAN.
I've found one article where it seems like this practice would not be recommended and causes issues. Noting that Exchange knows what IP (nic) the SMTP traffic points to, I don't see traffic segregation as being an issue. But, what I have in my head is only theoretical at best right now.
I've done individual research on the 'Requesting Data from Exchange Server' message and have made changes/tweaks based on what Microsoft would say in KB articles and various solutions I've found around here to no avail. The server itself is an HP ML350 w/ 4 gig of RAM and has all the data hosted on respective partitions on an HP SAN unit. I think the machine is spec'd well for the task and the SAN unit is very fast.
I think I've painted a pretty good picture of the scenario at hand. Please ask for any other information I may need to provide.