What is Managed Availability?

If there is one thing I have learned in my 20 years as a messaging architect, it’s that things change. Technology advances, new software becomes available, hardware becomes less expensive and/or more reliable.

Today I am here to talk about maybe the biggest change in Exchange 2013, Managed Availability.

Managed Availability is the packaged name for a number of new features in Exchange 2013 that are designed to keep your Exchange environment up and running without human intervention. Before I get to deep into explaining what Managed Availability is and how it works, I’d like to take a step back and explain the though process behind Microsoft’s decision to move Exchange in this direction.

The first thing it understand is that Microsoft no longer sees itself as a “software” company. Microsoft is in the process of re-organizing itself into a “devices and services” business. What this means to Exchange is that Microsoft sees a subscription to Office 365’s Exchange Online as a better solution for most customers than a license to the on-premises version of Exchange 2013. That is not to say that the on-premises version of Exchange is going away, but Microsoft is putting a lot more focus on Office 365.As Exchange Online continues to grow, Microsoft is very strongly incentivized to make the exchange service more reliable and less reliant on human intervention.  That brings us back to Managed Availability.

As I said above, Managed Availability is a group of features that are designed to keep Exchange 2013 services up and running for users without the need for human intervention. Exchange 2013 has a large number of “health probes” built in that are constantly testing all sorts of operations to ensure everything is working as expected. When something is found to not be working properly Managed Availability can step in and take action to improve that service. There are lots of possible actions that Managed Availability can take ranging from restarting a service to bug checking a server.

Wait…. Bug check a server? Isn’t that just a fancy way of saying…. Are you telling me that Exchange will intentionally cause the dreaded…


Yup, I said it. Exchange 2013 will in some circumstances cause your server to blue screen and that is a good thing.

Exchange 2013 has been designed under the theory that “Failure is an Option”. The idea is that a properly architected Exchange environment can withstand the failure of one or more servers without impacting the end-user experience and end-user experience is why we all come to work in the morning. Exchange 2013 has so many redundancy and resiliency features that a properly architected Exchange 2013 deployment will make automatic adjustments so survive all kinds of hardware and software failures.

This means that now more than ever, the proper deployment of a new Exchange environment is vital. Exchange 2013 was written to run very well on inexpensive commodity hardware, but if not properly deployed features like Managed Availability can make a real mess of your Exchange servers.