Route 53 - Health Checks

Question 1

What are the three types of health checks available in Route 53?

Answer 1

Endpoint Health Check: Monitors a public resource (e.g., a load balancer or server).

Calculated Health Check: Combines the results of multiple health checks into a single health check.

CloudWatch Alarm Health Check: Monitors a CloudWatch Alarm, useful for private resources.

Question 2

How do Endpoint Health Checks work?

Answer 2

AWS uses ~15 global health checkers to send requests to a public endpoint. If a majority of checkers receive a healthy response (e.g., 200 OK), the resource is considered healthy.

Question 3

What protocols are supported by Route 53 health checks?

Answer 3

HTTP, HTTPS, and TCP.

Question 4

What is the difference between regular and fast health checks in Route 53?

Answer 4

Regular Health Checks: Check every 30 seconds.
Fast Health Checks: Check every 10 seconds (higher cost).

Question 5

What is a Calculated Health Check?

Answer 5

A health check that combines the results of multiple child health checks using logical conditions (AND, OR, NOT).

Question 6

How can Route 53 monitor private resources like instances in a private VPC?

Answer 6

By creating a CloudWatch Metric, setting up a CloudWatch Alarm, and associating the alarm with a Route 53 health check.

Question 7

What network configuration is necessary for Endpoint Health Checks to work?

Answer 7

The health checkers must have access to the endpoint, so you need to allow incoming requests from the IP ranges of Route 53 health checkers.

Question 8

Where can you view metrics for Route 53 health checks?

Answer 8

In CloudWatch Metrics.