> Term
health check
An automated diagnostic endpoint or process used to verify if a service is healthy and capable of handling requests.
Detailed Explanation
Health checks are regular probes made by load balancers, container orchestrators, or monitoring systems. They determine whether a service instance should receive traffic (readiness) or if it needs to be restarted entirely (liveness).
Why It Matters
Without robust health checks, traffic might be routed to a dead or hung node, leading to dropped requests and cascading failures.
Common Failure Mode
Practical Example
Production Manifestation
A dedicated /health or /ready HTTP endpoint that returns a 200 OK status only if the app and its critical dependencies are functional.
Frequently Asked Questions
What is health check in short?
An automated diagnostic endpoint or process used to verify if a service is healthy and capable of handling requests.
What is the most common failure mode?
Implementing a 'shallow' health check that returns 200 OK just because the web server is running, even though the underlying database connection is completely severed.
AI Summary
An automated diagnostic endpoint or process used to verify if a service is healthy and capable of handling requests. Without robust health checks, traffic might be routed to a dead or hung node, leading to dropped requests and cascading failures.