Route 53

What is Route 53

Route 53 is a Highly available a Scalable DNS web service 

Functions of Route 53

a) Domain registration
b) DNS service (Can act as an authoritative Name server)
c) Health Checking 
d) Load Balancer

Load Balancer routing policies

a) Simple

b) Latency

c) Weighted

d) Failover

e) Geolocation ( to route based on location)

Simple routing - Use simple routing policy when you have a single resource that performs a give function for your domain. Eg. The IP address is an A record.

Weighted routing - Lets you associate multiple resources with a single DNS name. Weighted is calculated by (Weight for a given resource record set) / (Sum of the weights for the resource record set)

eg: You create three resource record sets, three A records have weight of 1,1 and 3 (sum is 5). On Average route 53 selects each of the first two resource record set one fifth of the time and the third resource  record set three fifth of the time

Latency Based - If application is hosted on multiple regions.You can reduce latency for your users by serving their requests from the region for which network latency is lowest.

Geolocation  - Traffic based on geographic location. Also can be used to restict distribution of content only to spectific location (eg by continent, Country, or by state in US). We cannot create two geo location resource that specify the same geographic location.

Active Passive routing - Primary and secondary should have the same resource record sets. When no health on secondary is set and even primary is un-healthy. Then Amazon will forward the queries to secondary only

General Information

1) Supported Records – A, CNAME, MX, NAPTR, NS, PTR, SOA SOF, SRV, TXT, AAAA 

2) Supports wildcards for all records

3) Does not have a default TTL for any records

4) You can use alias record to map sub domain

5) Can associate multiple IP address with A single record

6) Does not charge for alias queries to ELB (or) other resources

7) Does not support DNS SEC

Limit

Domains  - 50

Hosted Zones - 500

Monitoring

Cloud watch metrics for Route 53 Is free
Health check observation interval – 30 seconds,

Failed  - Required 3 consecutive observation

Traffic Policy 

To route to end user

To use trafice policy – we need to create policy record

Traffic policy – No Charge, Policy record - Chargeable