Route 53
A record:
A record value is always an IP address
A record maps your website like example.com to IP address (ex: Elastic IP)
CNAME:
CNAME can never be an IP address.
CNAME record maps a name to another name
CNAME are for actual DNS servers, you can't create a CNAME record for example.com
Ex:
An A record for example.com points to the server IP address
A CNAME record for www.example.com points to example.com
Alias:
Alias record is an Amazon Route 53-specific virtual record.
It works only with Amazon Route 53 (AWS specific resources)
AWS specific resources
ELB
CloudFront Distribution,
Elastic Beanstalks
S3 static websites
from one record in a hosted zone to another record.
A CNAME can’t be used for naked/root domain names. Root domain names must be mapped with either an A record or an Alias record (in Route 53).
AAAA Record:
AAAA record is similar to an A record but it is for IPv6 addresses
MX Record:
MX records (Mail Exchange records) is used for setting up Email servers
MX records must be mapped correctly to deliver email to your address
Simple routing policy
Route traffic to single resource
Failover routing policy
active-passive failover
Latency routing policy
You have resources in multiple AWS Regions and you want to route traffic to the Region that provides the best latency with less round-trip time
Geolocation routing policy
route traffic based on the location of your users
Geoproximity routing policy
route traffic based on the location of your resource
shift traffic from resources in one location to resources in another
Multivalue answer routing policy
you want Route 53 to respond to DNS queries with up to eight healthy records selected at random
return multiple values for a DNS query and route traffic to multiple IP addresses
Associating a Route 53 health check with records
Weighted routing policy
route traffic to multiple resources in proportions (based on weight 30% , 60% etc) that you specify.