Health check pattern in Microservices - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the health check pattern in microservices?

The health check pattern helps monitor if a microservice is running properly and ready to handle requests. It allows systems to detect failures early and take action like restarting or rerouting traffic.

beginner

Name two common types of health checks used in microservices.

1. Liveness check: verifies if the service is alive and not stuck.<br>2. Readiness check: verifies if the service is ready to accept traffic and perform work.

intermediate

Why should health checks be lightweight and fast?

Health checks run frequently and must not add heavy load or delay. Lightweight checks ensure quick responses so monitoring systems can react promptly without affecting service performance.

intermediate

How does a load balancer use health checks in microservices?

A load balancer uses health checks to decide which service instances are healthy and can receive traffic. It stops sending requests to unhealthy instances to maintain system reliability.

beginner

What could happen if a microservice does not implement health checks?

Without health checks, failures may go unnoticed, causing requests to fail or hang. This can degrade user experience and make recovery slower because the system cannot detect or isolate problems automatically.

Which health check verifies if a service is ready to accept traffic?

A Performance check

B Liveness check

C Dependency check

D Readiness check

Readiness checks confirm if the service is ready to handle requests, while liveness checks only verify if the service is alive.

What is a key characteristic of a good health check endpoint?

A Lightweight and fast response

B Long processing time

C Requires user authentication

D Heavy database queries

Health checks should be lightweight and fast to avoid adding load and to provide quick status updates.

How often are health checks typically performed in microservices?

A Every few seconds to minutes

B Once a day

C Only at startup

D Never

Health checks run frequently, often every few seconds or minutes, to quickly detect issues.

What role does a load balancer play with health checks?

A It shuts down unhealthy services

B It ignores health check results

C It routes traffic only to healthy instances

D It performs database backups

Load balancers use health check results to route traffic only to healthy service instances.

Which of these is NOT a benefit of implementing health checks?

A Early failure detection

B Increased service downtime

C Automatic traffic routing

D Improved user experience

Health checks help reduce downtime by detecting failures early, not increase it.

Explain the difference between liveness and readiness health checks in microservices.

Think about when a service is alive but not ready.

Describe how health checks improve reliability in a microservices architecture.

Consider what happens when a service fails without health checks.