Network Ports for Clients and Mail Flow in Exchange 2013

Published Mar 10 2015 08:26 PM 25.9K Views

Once upon a time in a land far, far away I wrote an article that told our action packed supportability story about the relationship of firewalls and Exchange servers. While the majority of response was positive to this purposefully lighthearted article (if you can’t enjoy your work why do it? :), there were other comments similar to the following:

“This isn’t official, it isn’t on TechNet!”

I’ll refer to the statement on the blog’s homepage:

This is the official blog of the Exchange Server Product Group.  All content here is considered authoritative and supported by Microsoft, unless otherwise specified.”

“It has a picture of cheese. I’m not using that as official guidance.”

You don’t like cheese? What did it do to you? Is it the smell? I’ll admit some of them do smell quite awful. I received a bruised toe from dropping a cheese wheel once.

“I don’t like spaghetti!”

Well that’s more for R5!

Terrible humor aside for a moment, we still recognized the need some of you had for something a bit more shall we say… polished. One of our wonderfully tenacious content developers, Chris Davis, took it upon himself to charge into battle and spent quite a bit of time tracking down everything required to put together this new article. In the end Chris has come up with a thorough TechNet article, without cheese, that we hope will provide you with everything required to stand up a perfectly healthy Exchange 2013 deployment all while staying within the support statement from the Exchange PG.

As a reminder we look at all Exchange servers across an entire organization’s deployment as one organic entity that rely on each other for proper function. Microsoft still does not support configurations when Exchange servers have network port restrictions that interfere with or alter communications with other Exchange servers, Active Directory servers, or Lync servers, as the new article states up front in much more clear wordage than before, and because of this the document focuses on client connectivity and mail flow into and out of the Exchange organization.

We hope the new article is put to good use and welcome commentary if there are any scenarios you feel we left out.

Brian Day
Senior Program Manager
Office 365 Customer Experience

Not applicable
Even though that all Exchange servers across an entire organization's deployment are seen "as one organic entity", it would be helpful to have a full picture of all ports being used by Exchange.

No serious administrator wants to configure port restriction that interfere with an Exchange deployment, but maybe it is a requirement to control and configure only the ports necessary. After 30 month down the road after RTM there is still no official port


This should not be that complicated, as each Exchange server is acting as an Island. Isn't it?

Not applicable
@Thomas, thank you for the feedback. The type of article you mention, which we had for earlier editions of Exchange, is exactly what lead to a massive amount of support cases and customer outages in the past when improperly followed/interpreted. Acting

in concert with the design philosophy of Exchange 2013 and v.Next, we are keeping it simple and easy to follow so there is no question on what is both supported & expected nor any chance of misconfiguration resulting in outages and lost company time.

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