SMTP Considerations for Unity Connection Single Inbox (i.e., Unified Messaging)

I think it is safe to assume that most of you know what the Single Inbox feature is all about.  However, Bill Bell once told me a little something about assumptions and he’s right a lot (except, of course, when he’s not).  Ok, so Single Inbox is a new feature introduced in Unity Connection 8.5, which provides Unified Messaging capabilities for customers that have Exchange 2003, 2007, and/or 2010.  Recently, I’ve looked at considerations for moving from good ol’ fashioned Unity Unified Messaging to Unity Connection with Single Inbox.  It’s important to note upfront that, while both provide the same feature (Unified Messaging), the method by which this is accomplished is quite different.  I’m not going to delve into that discussion here; however, you can refer to my CMUG presentation for more details here:

UC 8.x Applications Update

OK…so now that you’ve had ample time to review the CMUG presentation then let’s get on with it.  Aside from the obvious differences, I’ve also encountered some things that don’t appear to be laid out too clearly in existing documentation.  The first question generally is about the use of ViewMail for Outlook.  The main documented difference is that if you do not use ViewMail for Outlook then messages are simply treated as emails with .WAV attachments.  Given the proliferation of devices on which we can access data, there are inherently going to be questions about what that really means because it’s unlikely that 100% of your Single Inbox users will be using an Outlook client with ViewMail for Outlook installed at all times.  What this discussion translates into is a review of SMTP-related configuration points.  What I really want to see is more clarity in the documentation for Single Inbox that ties things together in a logical, cohesive manner.   For now, here is how I step through the scenario and look for things that may come into play:

Scenario

When Bill Bell leaves me a voice message on Unity Connection that is synced with my Exchange via Single Inbox, that message will have a reply address of mrscriptypants@cucxn01.thislabismylab.com.

NOTE:  The SMTP address/domain displayed is that of the Unity Connection server (cucxn01.thislabismylab.com), which is not the same as my corporate Exchange SMTP domain (thislabismylab.com).  This is basic messaging…no surprises, here.  Unity Connection mailboxes are assigned to an SMTP domain which, by default, is the FQDN of the server (or the Publisher in a cluster).  You can also optionally change the SMTP domain for Unity Connection; however, you should not set it to be the same as the corporate Exchange SMTP domain (not a good idea).

SMTP Considerations

• Configure Exchange to route mail destined for the Unity Connection SMTP domain to the Unity Connection server.

NOTE:  How you accommodate this within Exchange depends on which version you use. 

• By default, Unity Connection does not accept SMTP connections.  Configure Unity Connection to accept SMTP connections.

• Configure each Single Inbox user’s Message Relay actions to relay email messages to the user’s corporate (Exchange) email address.

• Unity Connection needs to be configured with an SMTP Smart Host.  I get a lot of questions about what “Smart Host” means so, for the record, it simply means a server that is configured to perform SMTP relay.  In this case, my relay server could be my Exchange server (exch01.thislabismylab.com).

• The SMTP Smart Host (i.e., SMTP relay server) needs to be configured to accept relays from Unity Connection.  Likewise, the relay server needs to know how to route messages for various domains.

NOTE:  How you accommodate this within Exchange also depends on which version you use.  There are also some other considerations (such as security) that come into play here as well.  The bottom line is that the Smart Host has to be “smart” enough to relay messages from Unity Connection to Exchange.