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Adding a 2nd Exchange Server for a different email domain on the same network

toe_mas asked
I am no server expert, but I can make my way around pretty well, with a little guidance :) So, here is my situation.

Company A created a new division that has turned into it's own company, Company B.
Both companies have their own domain name, companya.com and companyb.com
The MX record for companya.com points to the static IP address of a Windows 2000 server, running Exchange.
Companyb.com has all their mail forwarded from companyb.com to to an address at companya.com so it arrives in the same Exchange server.
They quickly outgrew the 16Gb limit of Exchange on the Windows 2000 server.
In the coming year(s) companyb will leave the facility where companya and companyb work out of, so they want their own separate server. I have a Windows 2003 Small Business Server I am setting up.

So, my current set up is a Windows 2000 server running a domain and running Exchange for companya.
A Windows 2003 SBS running a domain and soon to be Exchange for companyb
I am using a regular Linksys WRT54G router with an AT&T DSL Connection, with static IP.

What is the easiest way for mail for companyb.com to get to their 2003 server, and mail for companya.com to get to their server?

Thanks in advance!
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Technology and Business Process Advisor
Most Valuable Expert 2013
First, by using SBS now, you are pretty much breaking the companies up entirely now. SBS cannot have trusts so it will be it's own network.  Period.  You cannot install it in your existing domain (well, you can, but you shouldn't; there's a whole mess of complications that can occur).

Otherwise, you could just setup two MX records, one for each company, with different static IP Addresses.

Also, you do know that Exchange can handle e-mail for multiple domains without significant configuration work... No need for the forwarding.

You also realize if you upgraded to Exchange 2003 (from 2000) your information store could be nearly 5x larger...


Yes, I realize that, the two companies are separate and that is perfect.
There are two internal domains now, and that is how I want it also.
I knew that too, about multiple domains, but that was set up before I was doing the work here, and it worked, plus they were happy. So if it isn't broke, don't fix it :)
Yup, the new limit is 75 Gig, so I am quite happy with that.

As for now, they are in the same building with one internet connection, so the IP would be the same in both MX records.


P.S. Right now I am fighting with exmerge and moving mailboxes... I guess a manual export from the old server into a PST, then importing on the new won't work. I had tons of missing messages...


One server is more important than the other, would it work to have the less important server use the POP3 connector? Go out and get it's own mail 4 times an hour?
Top Expert 2008
>>would it work to have the less important server use the POP3 connector?

It could, but ideally you want to receive mail directly (assuming you have an IP address free, or are willing to use a reflector service)


The company has decided to get a separate internet connection with a static IP for the second Exchange server, so problem gone!
Thanks for the help

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