The migration path for the edge/director levels has two basic options. The first and simplest option is to deactivate and uninstall the existing Edge Servers and Directors with the intent to re-use certificates, DNS records, and IP addresses for the 2007 R2 components. However, if business continuity is a critical factor, with additional investments in certificates, IP addressing, and DNS configuration, a side-by-side edge environment is supported. Bear in mind during your planning for this evolution that a parallel 2007 R2 Edge/Director configuration that supports the 2007 R2 pool users must be totally separate.

If you intend to have a full side-by-side deployment for a while (Office Communications Server 2007 pool, Director and Edge, and an Office Communications Server 2007 R2 pool, Director, and Edge), you cannot have public IM and federation unless you create a different organization and sip domain. Only one side of the full side-by-side coexistence can have the requisite DNS records that belong to the SIP organization; therefore, the other side of the coexistence configuration will not be able to use those same records that represent your existing SIP domain. For details see the Deploying Edge Servers for External User Accessdocumentation.

If you are deploying a load-balanced array of Edge Servers, the next hop server on the Director must target the virtual IP address of the Access Edge service array on the internal load balancer. For details see Deploy Load Balancersin the Deploying Edge Servers for External User Access documentation.

An Office Communications Server 2007 Director is not a supported next hop for an Office Communications Server 2007 R2 Edge Server. The recommended approach for this phase is to deploy a Director and an Edge Server in tandem so that the Office Communications Server 2007 R2 Edge is not configured for a next hop of an Office Communications Server 2007 Director. Therefore, you should plan do one of the following: