Failover
The failover functionalities in G-SIM and G-Core are implemented at different levels to ensure maximum availability of the overall system (redundancy).
A distinction is made between the following levels.
- Management-Level (G-SIM Server-Failover)
- Recording-Level (G-Core Network Video Recorder (NVR)-Failover)
- Channel-Level (Camera-Failover)
All failover scenarios always require the use of G-SIM.
On this page you can find an overview of the different levels and the processes in the event of a failover.
G-SIM Server-Failover (Management-Level)
This level ensures that the management system (G-SIM) remains operational even in the event of a hardware defect of the main server.
How it works:
G-SIM is operated in a clustered environment with a primary server and a secondary server (failover-server).
Synchronization
The data between both servers is synchronized in real time, so that the data on both computers are identical.
The operator consoles (OpCon/ReCon) are connected to both servers to ensure seamless operation in the event of a failover. As soon as the primary server is available again, the system re-establishes the connection to it on its own. Failover servers can only operate continuously for 30 days within an outage. After these 30 days, the failover server stops.
NVR-Failover (Recorder-Level)
NVR failover secures video recording in the event that a physical recorder (NVR) fails completely.
Components:
NVR failover pools are configured. These consist of primary recorders and spare devices marked as "Global Spare". The use of “Agents” is absolutely necessary here, as they monitor the condition of the devices and control the failover process. The Agent backs up the setups of all primary NVRs in the event of a failover.
What happens in the event of a failover:
- If a recorder fails, an alarm is triggered.
- The system checks whether a replacement device (Global Spare) is available in the failover-pool.
- If this is the case, the setup of the failed device is automatically loaded onto the replacement device and recording continues there.
- In the operator console, the status (connected, available, failover operation) can be viewed via a special dialog.
Camera-Failover (Channel-Level)
This is the most detailed level where the failure of individual camera signals is compensated.
The prerequisite is that a failover-camera has been assigned to a camera.
What happens in the event of a failover:
- If a loss of camera signal is detected, the agent informs the server.
- The active viewer automatically switches to the failover camera.
Summary overview of processes
| Level | Trigger | System action |
|---|---|---|
| Server | Primary server unreachable | Operator consoles switch to secondary servers |
| NVR | Recorder Hardware Failure | Setup of the defective NVR is transferred to an available "Global Spare" recorder |
| Camera | Signal loss (sync loss) | System automatically switches to the associated failover-camera |