Topic Last Modified: 2010-11-07

The following are guidelines and best practices to consider when deploying Enterprise Voice:

Deploying Redundant Exchange UM Servers

Important:
We recommend that you deploy a minimum of two Exchange UM servers for each Exchange UM SIP URI dial plan that you configure for your organization. In addition to providing expanded capacity, deploying redundant Exchange UM servers provides high availability. In the event of an Exchange UM server failure, Lync Server can be configured to fail over to another Exchange UM server.

The following example configurations provide Exchange UM resiliency.


Exchange UM Example 1

In Example 1, Exchange UM servers 1 and 2 are enabled in the Tukwila data center, and Exchange UM servers 3 and 4 are enabled in the Dublin data center. In the event of an Exchange UM outage in Tukwila, the DNS A records for servers 1 and 2 should be configured to point to servers 3 and 4, respectively. In the event of an Exchange UM outage in Dublin, the DNS A records for servers 3 and 4 should be configured to point to servers 1 and 2 respectively.

Note:
For Example 1, you should also assign one of following certificate on each Exchange UM server:
  • Use a certificate with a wildcard in the Subject Alternative Name (SAN).

  • Put the FQDN of each of the four Exchange UM servers in the SAN.


Exchange UM Example 2

In Example 2, under ordinary operating conditions Exchange UM servers 1 and 2 are enabled in the Tukwila data center, and Exchange UM servers 3 and 4 are enabled in the Dublin data center. All four servers are included in the Tukwila users' SIP URI dial plan; however, servers 3 and 4 are disabled. In the event of an Exchange UM outage in Tukwila, for example, Exchange UM servers 1 and 2 should be disabled and Exchange UM servers 3 and 4 should be enabled so the Tukwila Exchange UM traffic will be routed to the servers in Dublin.

Note:
For details about how to enable or disable Unified Messaging on Exchange 2010 or higher, see: For details about how to enable or disable Unified Messaging on Exchange 2007 SP1 or higher, see:

See Also



    Example 2: Exchange UM Resiliency
    Example 1: Exchange UM Resiliency