4-Domain Name Systems Flashcards
Where is Route53 hosted?
It’s a global service with NS records stored in 4 regions.
It also operates at Edge Locations
What information do DNS servers host?
The Start of Authority (SOA) - details about the server and a default TTL for records
NS (name server) records are used by TLD servers to direct traffic to the Content DNS
One or more DNS records
What are the main kinds of DNS records?
A records translate domains to IPv4 IP addresses (AAA records are used for IPv6)
C names (Canonical names) resolve a domain to another i.e. a sub-domain or a redirect
Alias records are unique to Route53 - they map DNS names to an ELB or CloudFront etc. and automatically update if their underlying IP changes
What routing policies are available in Route53?
Simple - returned in random order
Weighted - weighted random order
Latency-based - lowest latency for the user
Failover routing - traffic is switched from the active setup to the passive setup if the former fails its HealthChecks
Geolocation routing - based on where the user is from
Multivalue Answer routing - multiple records, each with a health-check so it can return up to 8 healthy records
