VMware vCenter Server Heartbeat supports multi or single NIC configurations.
Public IP address: This IP address is used by a client to connect to an active server and move between primary and secondary servers in the event of a failover or switchover.
Channel IP address: This is for communication between the active and passive servers. This is used for control and data transfer from an active to passive server, and monitoring of an active server's status.
In a WAN, static routes are used over switches to maintain continuous communication.
Management IP address: This address is used to access servers in a passive role. In a multi NIC configuration, one NIC will have the Public IP and Management IP addresses, and another NIC will have the channel IP address. In a single NIC configuration, all IP addresses are on the same NIC.
