ROUTE 53
- Can purchase domains directly from Amazon
- Can take up to 3 days (usually 2 hours or less)
- Can set Health checks to remove failing records from routing, with notification if required
- ELBs do not have predefined IPv4 addresses, you resolve to them using a DNS name
- there is a default limit of 50 domain names. However, this limit can be increased by contacting AWS support.
- Main difference between CNAME and Alias
- Alias Records can also point to AWS Resources that are hosted in other accounts by manually entering the ARN
-- Alias can be assigned to apex domain (rajan.com - the non-www version)
-- CNAME cannot be assigned to apex domain

ROUTING POLICIES

- Simple Routing
-- One record with multiple IP addresses.
-- Serves any IP randomly

-Weighed Routing
-- can set weightage(percentage) of routing to records

- Latency-based routing
-- Allows you to route your traffic based on lowest network latency for end user (fastest response time)
-- Route53 will send traffic to instance with fastest response time
-- Can manually set latency-based routing

- Failover routing
-- Can set active and passive server and set failover based on instance status
-- Associate with health check, will failover if it fails health check

- Geolocation Routing
-- Lets you choose where traffic is routed based on geographic location of user

- Geo Proximity Routing (Traffic Flow only) 
-- Used to route traffic based on geo location of user and resources
-- Can also set how much traffic to set by setting ‘a bias’
-- To use, must use Route53 traffic flow

- Multivalue Answer Routing
-- Lets you configure Route 53 to return multiple values, such as IP addresses for serves
-- Can specify multiple values for almost any record, but multivalue answer routing also lets you check the health of each resource so only healthy resources are returned (slightly diff from  failover… no primary, both get love)