Exchange Maintenance is part of the routine operations when your Exchange environment is On-Premises. When Microsoft Outlook Web App was configured it is likely this traffic was load balanced and distributed across at least two Exchange servers with the Client Access Server Role (CAS). If this is case then it is relatively simple for your organization to remove a CAS from it’s responsibilities or add them back. It can be helpful to monitor the active OWA connections to better understand how many users are actively using any given CAS server in your environment at any time. This will let you know if load balancing is working correctly, but also when the user connections have been cleared.  Knowing how many connections your server is handling is also beneficial to ensure that there are enough server resources.  So there are many reasons why knowing how many active web connections your server has, and much value.

So, let’s take a look a how to monitor the active connections to your website.  Also, note that since versions of perfmon may vary.  Details on exact steps will be omitted.  High level content such as “add a counter” will be referenced instead.

Let’s get started!

• Run perfmon. You can either run it from the server in question or run it remotely and connect to the server.
• Open the Performance Monitor
• Access the Web Services -> Current Connections counter group
• Under the Current connections you will see each of the http websites for that server list as individual objects. Add Current Connection counters for each of the critical websites to be monitored.  Click OK.

web site performance counters

Note: While the example described this process could be used for OWA, it can also be used for SharePoint sites or any website that your organization requires a connection count.

• Change the properties of the graph so that the maximum values are in line with the connections being displayed.

From here the number of Microsoft Outlook Web App current connections can be monitored and when the quantity reaches zero for a site, the site can be removed from the load balancer or maintenance can be started for that server.  So, as you can see it can be quite helpful to be able to monitor active user sessions connected to your website. Enjoy!