Practical VoIP Using VOCAL

Heartbeat Server

The majority of VOCAL servers transmit regular pulses called heartbeats , which allow the other hosts on the network to determine whether any of the servers are down. The Heartbeat server manages the heartbeat flow. The following servers simply send heartbeats:

• Call Detail Record server

• Conference Bridge Marshal server

• Feature server

• Gateway Marshal server

• Internet Marshal server

• Policy server

• User Agent Marshal server

• Voice Mail User Agents

The following servers perform more complex tasks:

• Heartbeat server listens for heartbeats from all other components except for the Voice Mail User Agents.

• Provisioning server sends heartbeats and listens for heartbeats from the other Provisioning server (if a redundant server exists).

• Redirect server sends heartbeats and listens for heartbeats from the other Redirect server (if a redundant server exists), as well as from all Feature servers and Marshal servers.

• Voice Mail Feature server sends heartbeats and listens for heartbeats from only the Voice Mail User Agents.

The following servers neither send nor listen for heartbeats:

• Network Manager server

• Voice Mail server

The Heartbeat server is used by the Network Manager to update the GUI table of servers and server states. If your system does not include a Network Manager, the Heartbeat server is not required. For more information about network management, see Chapter 17.

Table 6-20 shows the provisioning tasks that can be performed with the Heartbeat servers.

Table 6-20. Heartbeat server ...