Route 53

Question 1

What is Route 53?

Answer 1

A highly available, scalable, fully managed and authoritative DNS (also a domain registrar)

Question 2

What are the most common record types of route 53?

Answer 2

A - maps a hostname to IPv4
AAAA - maps a hostname to IPv6
CNAME - maps a hostname to another hostname
NS - name servers for the hosted zone
ALIAS - points a hostname to an AWS resource (ELB, cloudfront, etc)

Question 3

What is a hosted zone?

Answer 3

A container for the records that define how to route traffic to a domain and its subdomains

Question 4

What are pros and cons of setting high/low TTL?

Answer 4

High TTL will generate less traffic on route 53 (less costs), but can possibly generate outdated records
Low TTL will generate more traffic on route 53 but records are outdated for less time, therefore it is easier to change records

Question 5

What are the routing policies and its use cases?

Answer 5

Simple:
* route traffic to a single resource
Weighted:
* control the percentage of requests that go to each specific resource
* traffic (%) = weight / sum of all weights
* use case: testing new application versions
Latency based:
* redirect to the resource that has the least latency close to us
* helpful when latency is a priority
Failover:
* when the healthcheck of the primary instance fails, use the second, disaster recovery instance
Geolocation:
based on user location:
* specify location by continet, country
use cases: website localization, restrict content distribution, load balancing
Geoproximity:
* route traffic to your resources based on grographic location of users and resources
* ability to shift more traffic to resources based on the defined bias
IP-based:
* based on client’s IP address
Multi value:
* use when routing traffic to multiple resources
* looks like an ELB, it’s a client side load balancing