Saner Watchdog Funtionailies in Saner CVEM Windows Agent

Product version: 6.5.0.0

Overview

This article explains the concept of a watchdog and how it plays a critical role in debugging and understanding the working principles of the Saner CVEM agent.

What is a Watchdog?

A watchdog timer (or simply "watchdog") is a software timer used to detect and recover from computer malfunctions. Its primary purpose is to monitor system operations and ensure that the system is functioning correctly.

Here’s a detailed breakdown of how watchdogs work:

1. System Monitoring

   • The watchdog software continuously monitors system operations, requiring periodic "heartbeat" signals to confirm normal functioning.

2. Fault Detection

   • If the system fails to send a heartbeat within the timeout period, the watchdog detects a malfunction. This could be due to software bugs, hangs, or unexpected failures.

3. System Recovery

   • Upon detecting a fault, the watchdog software typically restarts the affected component or service to restore normal operations.

Watchdog in Saner CVEM

In the context of SanerCVEM, the watchdog ensures that the spsaneragent service is always running smoothly.

• The file spagentwatchdog.log contains information about the status of the spsaneragent—whether it is running or not.
  

• This log is created by the executable spagentwatchdog.exe, which continuously monitors the agent service.

• If the agent service stops, the watchdog triggers it to start again automatically.

Example Log Behavior

When the agent service was manually stopped:

• The log recorded the service being stopped at 11:41 AM.
  

• The service remained in the stopped state for five minutes.
  

• Exactly after the five-minute interval, the watchdog restarted the service automatically, as confirmed by the logs.

This ensures minimal downtime and automatic recovery of the agent.

Task Scheduler Configuration

The watchdog process is defined in the Task Scheduler, which sets up a trigger to monitor the agent service:

• The configuration ensures that if the agent service is not running, it will be restarted every five minutes.
  

• This mechanism guarantees continuous operation and self-healing of the spsaneragent.

Conclusion

The spagentwatchdog.exe is responsible for generating logs and ensuring the continuous operation of the spsaneragent service.

• If the service is stopped, the watchdog records the event in the logs and restarts the service after five minutes.

• Task Scheduler confirms this behavior by showing a trigger set to monitor and restart the service at five-minute intervals.

This watchdog mechanism helps maintain reliability, stability, and uninterrupted functioning of the Saner CVEM agent.