When the Branch Session Manager (BSM) sends OPTIONS requests to the Survivable Communication Manager (CM)...

The Server ID is a numeric value that identifies each Communication Manager server in the network. The Server ID is used for licensing, administration, and synchronization purposes. Every CM server in the network needs to be assigned a unique Server ID, including servers in a duplex pair. A duplex pair is a configuration where two CM servers are connected by a dedicated link and act as a single logical entity, providing high availability and redundancy for call processing. The Server ID of each CM server in a duplex pair must be an even/odd pair (N, N+1), where N is an even number. For example, if one server in a duplex pair has Server ID 2, theother server must have Server ID 3. The Server ID can be configured during the installation or post-installation of Communication Manager, using the set server-id command