ELB Health Checks vs Route 53 Health Checks For Target Health Monitoring

Last updated on January 23, 2024

We all know that health checks are a very useful tool for making sure that AWS services such as AWS ELB and Amazon Route 53 know the state of their targets before forwarding traffic to them. In this section, we will take a look at ELB health checks and Route 53 health checks, and compare them with one another.

Health Check Service	AWS Elastic Load Balancing	Amazon Route53
What is it for?	This health check periodically sends a request to a target instance, server or function to verify its status i.e. available to accept traffic requests.	This health check monitors the state of a record’s target, which can be an EC2 instance, a server, or an AWS service that has an endpoint.
Target health check settings	You enter the port and common path of your targets that the load balancer will send the health check request to.	You enter the domain name or the IP address, port and patch that Route 53 will use to send the health check requests to if the record is a non-alias record, or by setting Evaluate target health to Yes if the record is an alias record.
Area span	Load balancers can monitor targets that span multiple availability zones but not multiple regions.	Route 53 monitors your targets regardless of their location, as long as they are reachable by Route 53.
Health check frequency	You specify a value between 5 seconds and 300 seconds.	Choose either every 10 seconds or every 30 seconds.
Response timeout	You can enter a value between 2 seconds and 60 seconds.	Cannot be configured.
Criteria to pass health check	You specify a threshold that a target a target should pass/ fail a health check to determine its status.	If more than 18% of health checkers report that an endpoint is healthy. Route 53 consider is healthy. If 18% of health checkers or fewer report that an endpoint is healthy, Route 53 considers it unhealthy. Route 53 health check servers are located in different locations worldwide.
Accessibility	Make sure targets are reachable by the load balancer. New targets can be easily added and removed from the load balancer.	Make sure endpoints are reachable and resolvable when users hit your URL. Due to DNS caching, it may take a while for new target endpoints to reflect end users.
Primary purpose	High availability and fault tolerance for your services.	DNS failover routing.

Written by: Jon Bonso

Jon Bonso is the co-founder of Tutorials Dojo, an EdTech startup and an AWS Digital Training Partner that provides high-quality educational materials in the cloud computing space. He graduated from Mapúa Institute of Technology in 2007 with a bachelor's degree in Information Technology. Jon holds 10 AWS Certifications and is also an active AWS Community Builder since 2020.