Microsoft Lync Server 2013 Front End: The Basics

By Nicole Spector Contributing Writer

Last February, the first cumulative update for Microsoft (News - Alert) Lync Server 2013 was released. In addressing that, Byron O. Spurlock, an independent consultant and trainer specializing in unified communications and messaging, covered some of the basics in his blog. 

Spurlock covers the following areas related to Lync Server 2013 Front End maintenance: Pool quorum; Upgrade domains and Best practices.

Spurlock writes that Lync Server 2013 has introduced the concept of a quorum. The introduction poses as a significant change from previous editions of Lync. Lync 2013 administrators need an elementary understanding of how quorums work with clustering. In order for a Lync 2013 Front End pool to be considered in a good and functional state, a certain number of Front End servers in the pool need to be up and running.

Spurlock provides the table below to delineate the number of servers that are required to be online and available in order for the Lync 2013 pool to be good to go:

 Lync Server 2013 Front End Quorum Reference

Total Number of Front End Servers in the Pool	Number of Servers that Must Be Running for Pool to Be Functional
1-2	1
3-4	2
5-6	3
7-8	4
9-10	5
11-12	6

If you are performing maintenance or patching Lync 2013 Front End servers and you happen to bring more than the appropriate number of Front End servers down, you'll get an error message in the Event viewer that reads "Local Pool Manager has been disconnected from Pool Manager."

As far as the upgrade domains and best practices are concerned, Spurlock points out that Front End servers in an Enterprise Edition pool are organized into upgrade domains. Upgrade domains are generated by Topology Builder when a Front End server is added and published. When upgrading Front End servers, one should perform the upgrades individually – one server at a time. It's best to bring a single server down, upgrade it, and then restart it before moving on to the next.

For more specific instructions on upgrading a Front End server with the Lync 2013 Cumulative Update, see Updates for Lync Server 2013.

Edited by Rory J. Thompson