7.76 Route 53 AWS Overview

In this section we explore AWS Route 53. We will cover the main features: record TTL (Time To Live), the difference between CNAME and Alias records, health checks, and the various routing policies — simple, weighted, latency-based, failover, geolocation and multi-value. We will also see how to bring an external domain into AWS via Route 53. Route 53 is AWS's managed DNS service. DNS is a set of rules and records that let clients find a server through a URL.

The most common record types used in Route 53 are A records, which map a hostname to an IPv4 address; AAAA records, which do the same for IPv6; CNAME records, which let you point a hostname to another hostname; and Alias records, which point a name to an AWS resource and return its underlying IPs.

How a DNS lookup flows

  • The client issues a DNS query for, for example, app.mon-domaine.com.
  • Route 53 returns the IP associated with that record (an A record for IPv4).
  • The browser then sends an HTTP request directly to that IP and gets the application's response back.

Route 53 can manage public domains that you own or buy through AWS (for example mon-domaine.com), but it also supports private hosted zones. A private zone like application1.ma-compagnie.internal resolves only inside your VPCs, which is perfect for internal services not exposed to the internet but reachable by other AWS resources. Beyond plain DNS, Route 53 offers advanced features: DNS-based load balancing (also called client-side load balancing), health checks against your instances — although these are relatively basic — and several routing strategies: failover, geolocation, latency, weighted and multi-value. A hosted zone costs about 50 cents per month. Next we will jump into the console and create our first Route 53 hosted zone for a domain we own.

Summary

Route 53 is AWS's managed DNS service that enables clients to resolve domain names to IP addresses and manage traffic routing across multiple strategies. This lesson covers core DNS concepts, key record types (A, AAAA, CNAME, and Alias records), and Route 53's advanced features including health checks, multiple routing policies, and support for both public and private domains.

Key points

  • Route 53 is AWS's managed DNS service that translates domain names into IP addresses using rules and DNS records to direct clients to application servers
  • DNS record types include A records (IPv4), AAAA records (IPv6), CNAME records (canonical names), and Alias records (AWS-specific resources), each serving different domain mapping purposes
  • Route 53 supports multiple routing strategies: Simple, Latency-based, Failover, Geolocation-based, and Multi-value answers to optimize traffic distribution and application availability
  • Route 53 handles both public domains (registered or purchased externally) and private domains (resolvable only within VPCs) for internal resource addressing
  • Advanced features include DNS-based load balancing and health checks to monitor instance availability
  • Hosting a zone in Route 53 costs approximately 0.50 USD per month

FAQ

What is the difference between public and private domains in Route 53?

Public domains (like application.domain.com) are accessible from anywhere on the internet and can be registered or purchased externally. Private domains (like application.mycompany.local) are resolvable only by instances within your VPC and are not accessible from outside your network, providing internal resource addressing within your AWS infrastructure.

What are the main DNS record types supported by Route 53?

Route 53 supports A records for IPv4 addresses, AAAA records for IPv6 addresses, CNAME records to alias one domain name to another, and AWS Alias records to map names to AWS resources. Each record type serves different purposes in DNS resolution and traffic management.

What routing strategies does Route 53 offer for traffic management?

Route 53 provides Simple (standard routing), Latency-based (routes based on lowest latency), Failover (routes to backup on failure), Geolocation-based (routes by geographic location), and Multi-value answers (returns multiple IP addresses for load distribution and high availability).