Route 53 Fundamentals

• Managed DNS
• Also work as a Domain Registerer

• Records

• A hostname to IPv4

• AAAA hostname to IPv6
• CNAME hostname to hostname

• Alias hostname to AWS resource

• Health Check

• Active-Active Failover
  • All resources should be available all the time
  • All records should be
  • Same name
  • Same Records
  • Same Routing Policy
• Active-Passive Failover
  • Primary Resource available all the time
  • In case of Failover, Secondary Resource always in standby
• Support
• A (Address Record)
• AAAA (IP V6 address record)
• CNAME (Canonical name record)
• CAA (Certification Authority Authorization)
• MX (Mail Exchange Record)
• NAPTR (name Authority Pointer Record)
• NS (Name Server record)
• SoA (Start of authority record)
• SPF (Sender Policy Framework)
• SRV (Service locator)
• TXT (Text Record)

• Not Supported

• DNSSEC

### TTL

• Stands for Time To Live
• Default value is 300 sec
• During this time the browser does not make the request to DNS server for IP
• When TTL is High
  • The server make less query to the DNS server
  • DNS server has low traffic
  • To change IP, need to wait long time
• When TTL is low
  • DNS server make DNS query more frequently
  • Easy to change the IP

CNAME vs Alias

• CNAME
• Points hostname to hostname
• Only works for non-root domain
• Alias
• Points to AWS Resource
• Works for both root and non-root domain
• Alias records is a AWS feature for its resources

Routing Policy

• Simple Routing Policy
• Send traffic randomly to the resources
• Weighted Routing Policy
• Send traffic multiple resource with specified percentage
• Latency Based Routing Policy
• Send traffic to the resource that has lowest latency
• Failover Routing Policy
• Active passive failover (Check the upper section)
• Geo location Routing Policy
• Send traffic based on users location
• Geo Proximity Routing Policy
• Send traffic based on resource location
• Multi-value Routing Policy
• Simple routing policy with health check

3rd Party Domains

• To import 3rd party domain to Route 53
• Create a hosted zone in Route53
• Update NS record on 3rd party website to use Route53