On the Exchange server, create the journal rules that define which recipients are journaled.
The domain name must be a non-existent domain. You must use the same domain for the remote domain, the mail contact, the Send connector, and the journal rules.
Before You Begin
You must have a thorough understanding of journaling and of managing journal rules on the Exchange server. Make sure that you understand the difference between standard journaling and premium journaling. Consult the Microsoft documentation before you create the journal rules. For example, see the article on the Microsoft TechNet site that corresponds with your version of Exchange.
Exchange 2016: "Journaling procedures in Exchange 2016", https://technet.microsoft.com/en-us/library/jj651670(v=exchg.160).aspx
Exchange 2013: "Manage journaling", https://technet.microsoft.com/en-us/library/jj651670(v=exchg.150).aspx
Exchange 2010: "Create a Journal Rule", https://technet.microsoft.com/en-us/library/aa995915(v=exchg.141).aspx
Exchange 2007: "How to Create a New Journal Rule", https://technet.microsoft.com/en-us/library/bb124723(v=exchg.80).aspx
If you use an Office 365 with Exchange using an on-premises Active Directory, create the same journal rules for the Office 365 with Exchange servers as for the on-premises servers so that all relevant messages that pass through your system are journaled.
Create a journal rule based on whether you use standard or premium journaling.
Consult the Microsoft documentation that is specific to your version of Exchange Server to determine the appropriate method for creating a journal rule.