Migration and Upgrades
If you've followed along in the book so far, you should have a good understanding of much of Lync, including how to deploy it. However, if you already have a Microsoft real-time communication platform in your environment, things are slightly more complex than if you don't. You will need to consider how to upgrade or migrate from one system to the next and negotiate a period of coexistence. Only migrations from Office Communications Server (OCS) 2007 R2 and Lync Server 2010 are supported. Any other older versions will require a “stepping-stone” approach to migrate to a supported start point prior to the final move to Lync Server 2013.
Of course, throughout this period you'll need to work with your users to make ...