Reference Architecture 2: Scaled Consolidated Edge (DNS Load Balanced)


Topic Last Modified: 2012-07-14

In the Edge Server pool topology, two or more Edge Servers are deployed as a load-balanced pool in the perimeter network of the data center. Domain Name System (DNS) load balancing is used for traffic to both the external and internal Edge interfaces.

If your organization requires support for more than 15,000 Access Edge service client connections, 1,000 active Lync Server Web Conferencing service client connections, or 500 concurrent A/V Edge sessions, and/or high availability of the Edge Server is important, this topology offers the advantages of scalability and failover support.

For simplicity, the following figure does not show any Directors deployed but in a real world production deployment they are recommended. For details about the topology for Directors, see Components and Topologies for Director.


The associated figure, topic on port summary and usage depicts the use of private IP addresses for the Edge Servers. You can also use public IP addresses for each Edge Server external interface and not use NAT. The use of public or private IP addresses is a choice that you make, but you should be aware that the use of public IP addresses increases the number of public IP addresses required for deployment. For details, see Choosing a Topology.


For clarity, the .com DNS zone represents the external interface for both reverse proxy and consolidated edge servers, and the .net DNS zone refers to the internal interfaces. Depending on how your DNS is configured, both interfaces could be in the same zone (for example, in a split-brain DNS configuration).

Hardware Load Balancer Configuration

For details, see the “Hardware Load Balancer Requirements for A/V Edge” section in Components Required for External User Access.


The Lync Server 2010 update that introduced mobility features – formally known as Cumulative Update for Lync Server 2010: November 2011 – is covered in detail in the Planning Mobility and Deploying Mobility sections. If you are planning to deploy mobility, refer to these topics for important planning and deployment information that will affect your decisions. For details, see Planning for Mobility and Deploying Mobility.

Scaled consolidated edge topology (DNS load balanced)

Scaled Consolidated Edge Topology