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Split Domain

What is a Split Domain?

A split domain will occur when you try to share your domain between two mail servers; where some users@YourDomain.com are on one mail server and other users@YourDomain.com are on another.

You will not be able to email anyone @YourDomain.com that is not on our Exchange servers.  The cause is that our system thinks that it is the authoritative email server for your domain, YourDomain.com.  So, when it gets an email addressed to a user@YourDomain.com that does not exist on our system, it rejects it - it doesn't know about your other mail server.

What can be done?

There are 2 options:

1. If each user at your current mail server has an alternative email alias that is *NOT* @YourDomain.com (i.e., YourCo.user@isp.com), then you can setup a forward from our system to each user.  (Just like the forwarding you can setup from the current mail server to us using the company.user@exchange.easystreet.com email aliases).
2. We can reconfigure your domain so that Exchange server redirects all unresolved email addresses @YourDomain.com to your current mail server.  However, there is a one-time setup fee of $20.00 for the manual setup.  This is the easiest & most seamless option.  Send an email to our Support team here with your company name, domain, and the other mail server's name to us.

When is it useful to have a Split Domain?

It is useful to have a Split Domain Configuration under two different scenarios:

1. If you are planning on migrating your users to Our Exchange environment over a long period of time; a 'slow migration'.

Why do you need a Split Domain?

A split domain will become necessary in either of the two scenarios above, because when the domain has been split between the two servers, email sent to users of the same domain, yet outside of the Exchange environment, will bounce.  The Exchange Server will only look within the Exchange Server for resolution.  Not recognizing the email address, it rejects it.

Typical Error code associated with a Split Domain problem: