What is a health-check mechanism for an EPD-supported system, and how is it used?

• A. A one-time health check performed at deployment
• B. Regular probes to verify subsystem readiness; used to detect faults and trigger recovery or failover
• C. A performance benchmark run quarterly
• D. A process for automatic software updates

Answer: (B)

A health-check mechanism is a set of regular probes that continually verify that each part of the system is up and ready to operate. In an EPD-supported setup, these probes check that subsystems can respond, dependencies are reachable, and resources are within acceptable limits. The key idea is ongoing visibility into health, not a single check done once.

This approach is the best because it lets the system detect faults early and automatically trigger recovery actions or a failover to a healthy replica. When a probe fails repeatedly, the orchestrator can restart the faulty component, reroute traffic, or bring up a replacement instance, keeping services available with minimal manual intervention. It’s about maintaining reliability through continuous, automated monitoring.

In practice, health checks are lightweight and run at intervals, often via health endpoints or monitoring agents. They focus on liveness (is the component alive?) and readiness (is it prepared to handle requests?), and they respond quickly so the system can respond with remediation steps if something goes wrong.

A one-time health check at deployment isn’t enough because issues can arise after deployment. A quarterly performance benchmark isn’t aimed at confirming ongoing health. Automatic software updates are a maintenance activity, not a health-check mechanism.