Health checks configuration in GCP - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of a health check in cloud infrastructure?

A health check monitors if a service or instance is working properly. It helps the system know when to send traffic to healthy instances and avoid unhealthy ones.

beginner

Name two types of health checks commonly used in Google Cloud Platform.

TCP health checks and HTTP(S) health checks. TCP checks if the port is open, HTTP(S) checks if a web service responds correctly.

beginner

What does the 'check interval' setting control in a health check?

It controls how often the health check runs to test the service's health, for example every 5 seconds.

intermediate

Why is it important to configure the 'unhealthy threshold' in a health check?

It defines how many failed checks in a row mark an instance as unhealthy, preventing false alarms from temporary glitches.

beginner

How does a health check improve the reliability of a load balancer?

The load balancer uses health checks to send traffic only to healthy instances, avoiding downtime and improving user experience.

Which protocol can be used for a simple health check that only verifies if a port is open?

A UDP

B HTTP

C HTTPS

D TCP

TCP health checks verify if the port is open and accepting connections.

What does the 'healthy threshold' setting specify in a health check?

A Timeout for each check

B Number of failed checks before marking unhealthy

C Number of successful checks before marking healthy

D Time between checks

The healthy threshold is how many successful checks in a row mark the instance as healthy.

If a health check timeout is too short, what might happen?

A Health checks run less frequently

B False unhealthy reports due to slow responses

C More traffic sent to unhealthy instances

D Health checks ignore errors

A short timeout can cause slow but healthy services to appear unhealthy.

Which Google Cloud service commonly uses health checks to manage traffic?

A Cloud Load Balancing

B Cloud Storage

C BigQuery

D Cloud Functions

Cloud Load Balancing uses health checks to route traffic only to healthy instances.

What is a key benefit of using HTTP(S) health checks over TCP health checks?

A They can check the actual response content and status code

B They are faster to run

C They use less network bandwidth

D They do not require a port number

HTTP(S) health checks verify the response status and content, ensuring the service works correctly.

Explain how health checks help maintain application availability in cloud environments.

Think about how traffic is managed when some servers fail.

Describe the key configuration settings of a health check and their impact on reliability.

Consider how often and how strictly the system tests the service.