two Exchange 5.5 servers accross two trusted domains

mogy · 28th January 2006

Hello,

I have a question about an exchange design between sites.

We have two domains, one NT4 and one AD. They are connected by a VPN. We have set up a two way trust between them and so file shares etc all work as expected.

The thing is that we also have two exchange servers, one on each domain. Completely different organisations. This is due to historical reasons. Basically in the past the two exchange boxes were set up for two separate companies and so everything was separate. However we have now decided to bring it all under one umbrella and reduce admin costs.

The exchange servers are like I said completely separate, even the email domain. We need to bring them onto our email domain. We do not need theirs. I am wondering what the best way to do this is. I can create them all a mailbox on our exchange server and then they can access the mail across the VPN. Their current emails would keep going to their old addresses though and so they would need to use outlook profiles as you cannot connect to more than one exchange mailbox. This does not appeal to me.

Is there a way for them to use their existing exchange server and we can just relay the emails on to them i.e. we collect all the mail for our domain and then send them on to them as required.

I am struggling with the connector side of this question and so any help would be much appreciated.

If I have missed anything off please let me know. I will be happy to fill in the blanks.

Thanks

Mogy

**Bursley** · 29th January 2006

Try checking out these articles:

http://support.microsoft.com/default...b;en-us;300141

http://www.msexchange.org/tutorials/...5_to_2003.html

The procedure of migrating can be done, but I would recommend upgrading your NT4 domain to Windows 2000 and join the forest of your existing organization.

mogy · 30th January 2006

Hello Bursley,

Thanks for the response. I ended up being offline yesterday and so did not get back to you sooner.

I have taken a look at the two articles that you mention. The thing is (assuming I have understood it correctly) that these both deal with moving the users to a new server. This is of course valid (and more correct than what I am looking to do) but it is not quite what I am looking for in the short term. I think I am looking to perform a function that is similar to the trust relationship with Windows. I would like us to keep our exchange set up and them to keep theirs (for now at least). I would like to set up maybe a trust relationship (if it exists in exchange) or should i be looking at connectors?

Thanks for your time on this

**ReggieB** · 30th January 2006

If you set up all users on the main Exchange box, you can then set the other Exchange system so that each mailbox forwards mail to the other. This can have issues - for example if you send an e-mail to two people in the forwarding domain, two forwarded emails will result. These then get forwarded to the other server which sees them as two new e-mails and forwards them to all addresses parsed in the header. The result: duplicate e-mails.

A simpler solution is probably to set up one Exchange box to handle both domains. Then you can set up the mailboxes of those who used the old domain, so that they have two e-mail address. User@maindomain.com and user@olddomain.com. Users could access the exchange box over the VPN. I think this is actually easier to set up on Exchange 5.5 than on later versions of Exchange - so don't be too hasty to upgrade.

I guess the problem is how many users you have. If less than 50, then manually setting up each mailbox isn't too much hassle. If hundreds, it may be a pain in the posterior.

Unfortunately it has been too long since I played with an Exchange 5.5 box, for me to remember the precise set up. But I am confident that you can set up 5.5 to handle two domains fairly easiliy.