Overview

Microsoft Lync Server has a number of different server roles. These can be combined different ways to produce a myriad of architectural options. Even the collocation of services for a given role can be split for added flexibility.

The Front End role in Lync Server is significantly changed from previous versions. Three significant architectural changes are related to the Front End Server role.

• The Office Communications Server 2007 R2 Mediation Server role is now collocated on the front end as a best practice for all architectures. The exception is a direct SIP connectivity to a PBX or a SIP trunking provider.

• The A/V Conferencing role can now be broken into a dedicated pool. This is recommended for large deployments with more than 10,000 users.

• The Director role is no longer simply a front end pool with no users assigned to it. It has been separated out to a unique role and is discussed further in Chapter 9, “Director.”

As in previous versions of Communications Server, a single Front End or multiple Front End Servers are organized into logical pools. A Standard Edition server exists as the only server in a pool, whereas multiple Enterprise Edition servers can exist in a pool to provide redundancy and scalability. HTTP traffic should still be load balanced by a hardware load balancer; however, other OCS services are now load balanced via DNS. This architecture moves complex traffic, SIP, and media off of hardware load balancers traditionally designed solely for HTTP traffic, and it simplifies the overall design.

This chapter highlights the full lifecycle of the Front End Server role. Because the Front End Server is deployed first, this chapter also reviews the steps necessary to prepare Active Directory. Then it moves on to the installation of the Standard and Enterprise Editions of the Front End Server role, followed by configuration and administration. Finally, the chapter concludes with troubleshooting and best practices.