The supported deployments of the Lync Server and the LoadMaster are described in the following sections. Multiple load balancers can be deployed for the Internal Pools, Internal Edge Server and External Edge Server. Single Load Balancers can be used to support both internal and external servers.

Lync Internal Server Deployment Options

Non-Transparent (Microsoft SNAT)

One-armed topology

This is the typical deployment method allowing the Load Balancer to be in the same network segment as the Real Servers.Two-armed topology

This topology requires a separate network for the Load Balancer and a separate network for the Real Servers. This requires more configurations networking wise and is considered not a typical deployment.

Transparent (Microsoft DNAT)

One-armed topology and two-armed topology

If you require that the client IP Addresses are retained when the LoadMaster forwards requests to the Lync servers, the transparent mode must be used.

Note: This topology is not supported as per Microsoft.

Lync External Edge Server Deployment Options

One-armed topology & two-armed topology

Transparency must be used when working with load balancers (at least for the Audio and Video EDGE Server).