Microsoft® Lync® Server 2013 Unleashed Second Edition

Centralized Sign-In

Based on the previously described sign-in process, administrators without a Director in a multiple Front End pool environment face a dilemma of determining which pool should handle the initial sign-in and authentication for all users. The Lync client applications use weighted DNS SRV record lookups to find a pool, and only one pool can be considered the most preferred. When a Director exists, these DNS records typically point at the Director, which then handles sending the user a SIP 301 Redirect message with the primary and backup registrar pool information. Without a Director, one of the Front End pools in the environment must be responsible for handling these tasks for all users.

Historically, the Director role played a ...