AWS Route53

what is Route53

In AWS, Route53 is a global managed DNS (Domain Name System) &  DNS is a collection of rules and records which helps clients understand how to reach a server through URLs.

DNS operates on port 53. Amazon calls it route 53 so that’s where the name comes from.

It’s a global service. You need to buy a domain in order to work with Route53, Go to Route53 Service & Click on register domain. Enter the domain name & check availability, Add to cart & click on continue.

Route53 can use basically:

• Public domain names you own (or buy) or Private domain names that can be resolved by your instances in your VPCs.
• Route53 has many features such as Load balancing, Health checks, Routing policy like Simple, Failover, Geolocation, Latency, Weighted, Multi-value.
• You pay $0.50 per month per hosted zone.

Route53– Managed DNS(Domain Name System) in AWS.

DNS: Collection of rules & records

Route53 uses:

• Public Domain (You own)
• Private Domain ( Inside your VPC for your instances)

Route53 Features:

• Health Checks
• Load Balancing through DNS
• Provides different kinds of Routing Policy.

Types of Records:

• A Record -Hostname to IPv4
• AAAA -Hostname to IPv6
• CNAME- Hostname to Hostname
• Alias- Hostname to AWS Resources

TTL (Time to live):

• DNS cache for TTL duration. It’s mandatory for all kind of records.
• Max TTL: 24hrs
• Min TTL: 60 seconds

Health check:

• Monitor the health and performance of your application’s servers, or endpoints, from a network of health checkers in locations around the world. You can specify either a domain name or an IP address and a port to create HTTP, HTTPS, and TCP health checks that check the health of the endpoint.
• Health check failed: Unhealthy if 3 health checks get fail.
• Health check passed: Healthy if 3 health checks get pass.

Alias VS CNAME:

Alias: Hostname to AWS Resource, works for root domain & non-root domain both.

CNAME(Zone Apex): hostname to hostname, only work for the non-root domain (it means, CNAME’s record name can’t be the same as hosted zone name).

Routing Policies:

Simple Routing: redirect to a single resource, can’t attach health check, If multiple records are attached, a random one will be selected.

Weighted Routing: “N” % requests will go to a specific Endpoint, It’s helpful to test 5–10% traffic on the new application version, can attach a health check.

Latency Routing: redirect to the server that has the least latency close to us, latency is calculated in terms of AWS Region, health check attached.

Failover Routing: If the primary resource is not working, traffic is redirected to the secondary instance/resource. A health check is mandatory.

Geo-location Routing: routing is based on user location. Specify that, traffic from the XYZ location should go always to a particular instance/resource, if it doesn’t match, should go to default policy(We define this also).

Multi-Value: Use when, traffic needs to go to multiple resources, health check mandatory. It’s not a substitute for having an ELB.

DOMAIN REGISTRAR is not equal to DNS.

If you have bought a domain from 3rd party (eg: Go Daddy), you can use it in AWS Route53 by creating a hosted zone in Route53 & update NS records on 3rd party website to use Route53 name servers.