Route53

Domain Management Service (DNS Solution) for AWS (or other clouds/bare metal if you want)

Essentials

• Key Features:

  • Domain Registration

    • Register domain names like nicacton.com

  • Domain Name System (DNS) Service

    • Translates friendly domains to IP addresses

    • Responds to DNS queries using a global network of authoritative DNS servers (almost no latency)

  • Health Checking

    • Sends automated requests over the Internet to your app to verify its reachable, available, and functional!

• Can manage external DNS for domain routing to proper AWS resources like: a Cloudfront distribution, ELB, EC2 instance or RDS server via Alias records

• Commonly used with ELB to direct traffic from the domain to the ELB (thus evenly distributing traffic among servers)

• Can be used to manage internal DNS for custom internal hostnames within a VPC as long as the VPC is configured for it.

• Latency, GEO, basic, and failover routing policies allow for region-to-region fault tolerant architecture design. GLOBAL propagation, usually in less than a minute!

• You can easily configure for failover to S3 (if website bucket hosting is enabled.)

Hosted Zones

• Stores DNS records for your domain

• Contains all the rules (record sets) that tells Route53 what to do with DNS requests.

• There are both public and private hosted zones:

  • Public - Holds information about how you want to route traffic on the Internet for a domain, such as nicacton.com, and it's sub-domains

  • Private - Holds information about how you want to route traffic for a domain and its subdomains within one or more AWS VPCs

• After you create a hosted zone for your domain, you create resource record sets to tell the Domain Name System (DNS) how you want traffic to be routed for that domain.

• Hosted zones come pre-populated with NS (name server) and SOA (start of authority) record sets.

Record Sets

• Record sets are instructions that actually match domain names to IP addresses

• Options:

  • Record type

  • Standard/alias

  • Routing policy

  • Evaluate target health

• Common Record Types

  • A: Point a domain to an IPv4 IP

  • AAAA: Point a domain to an IPv6 IP

  • CNAME: Point a host/name to another host/name

  • MX: Used to route email (mail exchange)

• Alias Record Sets

  • Instead of an IP Address (standard record sets), an alias record set contains a pointer to an AWS specific resource, such as:

    • An elastic load balancer

    • Cloudfront distributions

    • Elastic Beanstalk environments

    • Amazon S3 bucket configured as a static website

• Routing Policy

  • Simple - Route to one endpoint

  • Weighted - Divide traffic to multiple endpoints (manual load balancing)

    • Good for testing of new environments

  • Latency - Resolve to Load Balancer or resource that is closest to the client making the request

  • Failover - Disaster recovery, if first instance is not healthy/unavailable it should return a second endpoint

  • Geolocation - Want to send users to a particular endpoint based off IP Location (country regions, like .uk)

• Evaluate Health Check

  • Can monitor the health of your application and trigger an action.

S3 for DNS Failover

• By using a failover routing policy in a Route53 DNS record set, an S3 bucket can be used as a failover endpoint.

• This is an extremely reliable backup solution if your primary endpoint fails.

• Even though S3 should only be used for static web hosting, it can be used to provide information until the primary endpoint is working again.

• S3 can also be used as the primary endpoint if you just want to host a static site on it.

  • For a DNS record to use an S3 bucket as an endpoint, the bucket name must match the domain name