Does Symphony support N+1 operation?
Yes. For TDM systems, a hardware switching unit is available that supports N+1 configurations.
Symphony is designed to provide resilient recording to the organisations that deploy it. Sentinel is the Symphony component responsible for monitoring the health of all Symphony components.
It can monitor individual services to ensure that they are functioning.
It provides SNMP heartbeat support to allow external systems to verify that the system is fully functional.
It monitors usage of various system resources.
It allows status information from third party components such as RAID controllers to be written to the system audit logs.
It manages the hardware watchdog chips available on the motherboards recommended for use with the system.
It includes support for an external alarm panel device which allows system alarms to be presented at a remote location.
It manages automatic failover when used in conjunction with the TDM switching array.
The following is an example of a mixed media system configured to record TDM and VoIP in an N+1 redundant configuration using NetStore GateWay to provide data security in real time.
In the above configuration, Sentinel runs on the Secondary unit. It monitors the health of the Primary recorders over the LAN and caches their configurations locally. If the configuration of one of the monitored Primary units changes then Sentinel receives an automatic notification and it updates the cached data it holds for that unit.
If Sentinel detects a failure on one of the Primary units it does the following:
Enables the Secondary Unit.
Switches ALL signals that were presented to the failed Primary unit to the Secondary unit.
Disables the Primary unit if is still connected to the network.
Uploads the cached configuration that it holds for the failed unit to the Secondary unit.
Re-establishes the recording states on the Secondary unit.
Raises a series of warnings detailing the precise error conditions that caused the failover.