In this series, I am going to document installing Skype For Business into my environment. Before jumping into the install, the first step is planning and assessing your current environment and your requirements. Then, develop the Skype For Business Architecture that fits your requirements and current environment.
There is extensive documentation on the Skype For Business planning process on TechNet (here)
In my case, I have a Lync 2013 environment with 3 Front Ends, 2 SQL 2012 Back-End Database servers and a Lync 2013 edge.
I want to go to a Skype For Business (SfB) pool with 3 Front Ends, SQL Back-end, SfB Edge, and hybrid configuration with Office 365.
THE FIRST THING that I noticed was that in this configuration that I can’t do an in-place upgrade (without having downtime ). Yesterday, I wrote about SfB ability to support in-place upgrades. However . . .
If you have only ONE Lync Pool then you can’t do an in-place upgrade (without downtime).
The reasons is that to perform an in-place upgrade, you need to have at least 2 Lync pools. You move users from one Lync pool to the second Lync pool. Then upgrade the first Lync pool to Skype For Business (SfB). In the upgrade process, the first pool is shut down while the upgrade is happening and until all the Lync Front-End servers in the pool are upgraded.
In my scenario, although I have 3 Lync 2013 Front End servers, they are all in one Lync pool. My option in this scenario is to setup a new SfB pool and then move users from the Lync 2013 pool to the new SfB pool.
LESSON LEARNED: You should only consider an in-place from Lync to Skype For Business (SfB) if you have more than one Lync pool.