Q: Implementing an OS X Server as our mail server.

If you were on Exchange, you are not going to be happy moving to OS X's groupware solution.  I strongly encourage you re-evaluate the decision.  Exchange makes a good mail server because nearly everything supports it.  From OS X to iOS to Android to Windows.  Nearly everything has Exchange connectivity built in.  Apple's offering is IMAP (which is generally supported across everything), CalDAV, and CardDAV (both of which have limited choices outside of OS X and iOS).  These technologies can work well in an all Mac environment but really struggle to solve a cross-platform environment.

Here are a few things to consider in this day and age.  First, self hosting of mail is asking for service disruption.  Regardless of the server selected, there is a good chance you have one internet connection, one firewall, one switch, one power circuit, and one server.  In the case of Apple, the server may be a Mac mini. Which while reliable, is still a consumer product encouraged to act as a server.  There is one internal drive and no redundant components.  Even with AppleCare, you are looking at a three day window for repair.  Can you be without mail for 3 days or longer?

Next, as hinted above, OS X Server does not make a great mixed platform groupware solution.  As you asked above, you can not bind Windows devices to Open Directory.  You can bind Macs to Active Directory.  In a mixed platform deployment, Windows servers win outright.  Now, if you want to roll your own SAMBA deployment, you would be able to integrate both Macs and Windows devices into a common non-AD domain.  But there is significant effort in this process.  Back to the groupware.  Check out these two sites for the details on CardDAV and CalDAV clients:

http://carddav.calconnect.org/implementations/clients.html

http://caldav.calconnect.org/implementations/clients.html

You will notice that Outlook is not listed in either of the lists.  The list does contain plugins however.

I would suggest that you look for a cloud partner to host your mail.  If you can not (for compliance, security, etc) host your mail outside of your environment and you absolutely must get away from Exchange, then look at Kerio Connect.  First, you have Exchange compatibility so now you can support most platforms without acrobatics.  Next, the spam and virus protection offerings are built in, easy to setup, easy to learn, and effective.  Kerio also has a back up feature built in and the latest version supports clustering.

Please don't get me wrong.  I am huge fan of OS X Server.  It is a great solution for many different problems.  I just don't like the groupware solutions (or lack there of).  Cruise these forums to find the nightmare that is Apple's mail server.  Difficult to configure and nearly impossible to troubleshoot when something goes wrong.  If mail is critical to your business, you should be looking elsewhere.

Reid

Apple Consultants Network

Author - "El Capitan Server – Foundation Services"

Author - "El Capitan Server – Control & Collaboration"

Author - "El Capitan Server – Advanced Services"

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