Amazon Route 53 Routing Policies: A cornerstone component in improving performance & availability
Tags: aws, route53, dns, beginners
Published: 2023-10-20 12:07:00

Dealing with Amazon Route 53 is one of my favorite tasks. The main reason behind this is that AWS had invested a lot of effort into designing its DNS (Domain Naming Service) which made it superior to other alternatives in the market. Another reason is that the service is elegantly named. Indeed embedding the DNS service port number into the service name was a smart decision made by AWS. Having that said, let’s now delve into more details of the Amazon Route 53 service.

[Amazon Route 53 is a highly available and scalable Domain Name System (DNS) service](https://aws.amazon.com/route53/) that allows users to route end-users to internet applications. AWS Route53 is a versatile service that can be used to manage domain registration, create and manage DNS records, and configure health checks to monitor the health and performance of resources. In this article, we’ll take a closer look at the different routing policies offered by AWS Route53 and how they can be used to optimize the performance, availability, and cost-effectiveness of internet applications.

Before diving into the routing policies, it’s important to [understand how DNS works](https://en.wikipedia.org/wiki/Domain_Name_System). DNS is a hierarchical naming system that maps human-readable domain names to IP addresses that computers use to connect to each other. DNS servers are responsible for storing and distributing DNS records that contain information about domain names and their associated IP addresses. When a user types a domain name into their web browser, the DNS server looks up the associated IP address and directs the user’s request to the appropriate web server. _Note that_ All IP rights to this blog post are reserved. Since I have been facing several content piracy cases lately, this blog post has ONLY been published on [the Software, Architecture, and Cloud blog - SWAC.blog](https://swac.blog) and canonically to [dev.to](https://dev.to/khalidelgazzar) only. If you are reading it elsewhere, then [please let us know](https://swac.blog/contact-us/)

AWS Route53 offers several routing policies that can be used to control how DNS requests are routed to internet applications. As of the time of writing, Amazon Route 53 provides 7 different routing policies. Let’s examine each policy in more detail:

1\. Simple Routing Policy
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The [Simple Routing Policy](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-simple.html) is the most basic routing policy offered by AWS Route53. With Simple Routing, you can route traffic to a single resource such as an Amazon Elastic Compute Cloud (Amazon EC2) instance, an Amazon Simple Storage Service (Amazon S3) bucket, or an Elastic Load Balancer (ELB). You can also specify an IP address as the destination for Simple Routing. Simple Routing is useful when you have a single resource that you want to route traffic to, such as a website or a web application.

2\. Weighted Routing
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[Weighted Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-weighted.html) allows you to route traffic to multiple resources in proportions that you specify. For example, you can route 50% of traffic to one Amazon EC2 instance and 50% of traffic to another Amazon EC2 instance. This can be useful for load balancing and testing new application versions. You can also use Weighted Routing to route traffic to resources in different AWS regions to optimize performance for users in different parts of the world.

3\. Latency-Based Routing
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[Latency-Based Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-latency.html) allows you to route traffic to the resource that provides the best latency to the user. This can be useful for optimizing the performance of applications that are accessed by users in different geographic locations. AWS Route53 measures the latency between the user and each resource, and routes traffic to the resource with the lowest latency. Latency-Based Routing can be used to route traffic to resources in different AWS regions to optimize performance for users in different parts of the world.

4\. Failover Routing
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[Failover Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-failover.html) allows you to route traffic to a standby resource in the event of a failure of the primary resource. For example, you can route traffic to a secondary Amazon EC2 instance if the primary instance becomes unavailable. Failover Routing can be useful for ensuring high availability of critical applications.

5\. Geolocation Routing
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[Geolocation Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-geo.html) allows you to route traffic to a resource based on the geographic location of the user making the request. This can be useful for ensuring that users are directed to resources that are geographically closer to them, which can improve performance and reduce latency. Geolocation Routing can also be used to route traffic to resources in different AWS regions to optimize performance for users in different parts of the world.

6\. Multi-Value Answer Routing
------------------------------

[Multi-Value Answer Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-multivalue.html) allows you to return multiple values in response to a DNS query. This can be useful when you have multiple resources that can handle a request, such as multiple Amazon EC2 instances or multiple IP addresses. Route53 returns up to eight healthy records in response to each DNS query, which can help distribute traffic across multiple resources and improve availability. You can also enable health checks for Multi-Value Answer Routing to ensure that only healthy resources are returned in response to DNS queries.

7\. Geoproximity Routing
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[Geoproximity Routing](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-geoproximity.html) allows you to route traffic to a resource based on the geographic location of the user and the resource. This routing policy works only with [Traffic flow](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/traffic-flow.html) which is an AWS tool to graphically define regions within Route 53. Geoproximity Routing can be useful for optimizing the performance of applications that are accessed by users in different parts of the world. Route53 uses geolocation data from AWS resources and third-party providers to determine the location of the user and the resource, and routes traffic to the resource with the lowest latency. Geoproximity Routing can be used to route traffic to resources in different AWS regions to optimize performance for users in different parts of the world.

Conclusion
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AWS Route53 is a powerful and flexible DNS web service that can be used to route end-users to internet applications. It offers a range of routing policies that can be used to optimize the performance, availability, and cost-effectiveness of Internet applications. The routing policies include Simple Routing, Weighted Routing, Latency-Based Routing, Failover Routing, Geolocation Routing, Multi-Value Answer Routing, and Geoproximity Routing. These policies can be combined and customized to meet the specific needs of different applications.

One of the key benefits of using AWS Route53 is its ability to route traffic across different AWS regions. AWS has multiple regions around the world, and using Route53 to route traffic to resources in different regions can help optimize the performance of applications for users in different parts of the world. Route53 also integrates with other AWS services such as Amazon EC2, Amazon S3, and Elastic Load Balancing, which makes it easy to manage and configure DNS records for these services.

In conclusion, AWS Route53 is an essential tool for managing DNS and routing traffic to internet applications. By understanding the different routing policies and how they can be used, you can optimize the performance, availability, and cost-effectiveness of your applications. Whether you’re running a small website or a large-scale web application, AWS Route53 has the flexibility and scalability to meet your needs. _Lastly, note that,_ All IP rights to this blog post are reserved. Since I have been facing several content piracy cases lately, this blog post has ONLY been published on [the Software, Architecture, and Cloud blog - SWAC.blog](https://swac.blog) and canonically to [dev.to](https://dev.to/khalidelgazzar) only. If you are reading it elsewhere, then [please let us know](https://swac.blog/contact-us/)

***For more articles about AWS & how to begin your AWS journey,*** visit AWS section on the [Software, Architecture & Cloud blog - SWAC.blog](https://swac.blog/category/cloud-computing/aws/)