AWS Route53 Deep Dive

AWS Route53 Deep Dive

January 8, 2021 / Nirav Shah

Before dive into this, we assume that you already know DNS service in TCP/IP protocol

• You can use Amazon Route53 to register new domains, transfer existing domains, route traffic for your domains to your AWS and external resources & monitor the health of resources.
• It’s a service like DNS (Domain Name System) in TCP/IP Protocol.
• It also supports IPV6
• Route53 is Global Service which means that you can access this service from any region.

Route53 name history

• The reason is that DNS has TCP Port is 53, So that’s why we called it as Route53 Service in AWS.
• In the US the busiest and traffic way is Route53, So that’s why AWS give this service name as Route53. 

Route53 Functions:

DNS management

A hosted zone tells Route 53 how to respond to DNS queries for a domain such as example.com.

Traffic management

A visual tool that lets you easily create policies for multiple endpoints in complex configurations.

Availability monitoring

Health checks monitor your applications and web resources, and direct DNS queries to healthy resources.

 Domain registration

A domain is a name, such as example.com, that your users use to access your application.

Route53 Performs three main functions,

1. Register a Domain, for example, www.eternalsoftsolutions.com
2. As a DNS it also routes the internet traffic to your resources for your Domains.
3. Check the health of your resources.

You can use Route53 any combination of the functions,

• For Ex. You can use Route53 for the register your domains and route internet traffic to your resources
• You can use Route53 to route internet traffic for a domain that you have registered with another domain registrar. Ex. GoDaddy

When you register our domain with Route53 the service automatically create DNS service for the domain by doing the following.

• It creates a hosted zone that has the same name as your domain.
• It assigns a set of four name server to the hosted zone, unique to the account

AWS Supports:

1. Generic top level domains 
   Ex. .com, .org, .net ,Etc
2. Geographic top level domains 
   Ex. For india – .in, For US – .us, For China – .cn , Etc

AWS Limit

Each AWS Route53 account is limited to a maximum of 500 hosted zones and 10,000 resources record sets per hosted zone. 

Note- You can increase by requesting to AWS Support

Support DNS Records type by Route53

• NS Record – Name server record. Used for delegating hostname to name server. NS record defines which name server is authoritative for a particular zone or Domain name and points you to another DNS server.
• SOA Record – Start Of authority record. Every single zone has one and only one SOA resource record at the beginning of the zone.
• It is not an actual record, it includes below information,
  • Who is the owner of the domain and its associated email address.
  • The authoritative server information.
  • The serial number which is incremented with changes in zone data.
  • The refreshing time cycle info and the TTL 
• A Record – Address record. Map IP address to a unique domain.
• AAAA Record – Use for IPV6 address record. Map IPV6 address to a unique domain.
• CNAME Record – Canonical Name Maps an alias name to the hostname. Can create for subdomains. We can not create it for the root domain.
• MX Record – Mail exchange record. Define where to deliver the mail for a domain name.

AWS Route53 Routing policies:

When you create any record, you choose routing policies which determine how Amazon Route53 responds to the queries.

• Simple routing policy – In this DNS policy we can accommodate a single FQDN (fully qualified domain name) or IP address. For A record, you can enter the IP address as the value. For load balancers, you can use CNAME.
• Failover routing policy – Failover routing allows you to route traffic to a resource when the resource is healthy and to another resource when the first one is unhealthy.
• Geolocation routing policy –Geolocation Routing Policy allows access to the resources based on the geographic location of the users or client.
• Geoproximity routing policy –Use for routing traffic based on the location of resources and, optionally, shift traffic from resources in one location to resources in another.
• Latency routing policy – Use when you have resources in multiple AWS Regions and you want to route traffic to the region that provides the best latency.
• Multivalue answer routing policy – Use for responding to DNS queries with up to eight healthy records selected at random.

Weighted routing policy – In this you can  weight per subnets.You create records that have the same name and type and assign each record a relative weight.To stop sending traffic to a resource you just need to change the weight of the record to 0.