HA Architecture

High Availability is systems with
- minimum downtime
- minimum service interruption
Implement HA by
- eliminate single points of failure in infrastructure
- putting redundant components for same task
- adding the load balancer above it, to detect failures and adapt for timely recovery

Failure Points	AWS Services/Solution
DNS/Domain Services	Route53
Load Balance	Elastic Load Balancing
Web/Application Server	Auto-Scaling
Database Servers	Redundant nodes or clustering
Authentication	Redundant nodes
Data Center Failures	Use Multiple Availability Zone
Disaster	Use Multiple Regions