Loss of failover when load balancing Edge pools using DNS is possible in the following scenarios:

  • Federation with organizations running Office Communications Server (OCS) versions older than Lync 2010
  • Privileged Identity Management (PIM) connectivity with Skype, Windows Live, AOL, Yahoo!, and XMPP partners
  • Unified Messaging (UM) Play on Phone functionality
  • Transferring calls from UM Auto Attendant