Global Infrastructure

1. Availability Zones (AZs)

Availability Zones (AZs) enhance high availability and fault tolerance by distributing resources across geographically separated locations within an AWS Region.

  1. Geographic Isolation: Each AZ is physically separated and located in a different geographic area, typically a few miles apart, within a region. This means that an issue in one AZ (like power failure, hardware failure, or natural disaster) doesn't affect the others.
  2. Fault Tolerance: AZs are connected through low-latency, high-throughput networking, which allows seamless failover between them. For example:
    1. Amazon EC2 instances can be spread across multiple AZs, and if an instance in one AZ becomes unhealthy, Auto Scaling can replace it with a healthy instance in another AZ.
    2. Amazon RDS provides Multi-AZ deployments for database replication, so if the primary database instance fails, the secondary instance in another AZ automatically becomes the new primary.
  3. With services like the Elastic Load Balancer (ELB), traffic can be distributed across instances in multiple AZs. If one AZ experiences an issue, the load balancer will route traffic to healthy instances in other AZs.

2. Types of Services

  1. Global Services: Accessible across all regions, not tied to a specific region. Examples: IAM, Route 53, CloudFront.
  2. Regional services: Operate within a specific AWS region, spanning multiple Availability Zones. Examples: EC2, RDS, Lambda.
  3. Zonal services: Tied to a specific Availability Zone and deployed into that AZ. Examples: EC2 instances, EBS.

3. AWS Global services

  1. Route 53 – Global DNS service.
  2. IAM
  3. AWS Global Accelerator
  4. CloudFront
  5. AWS Organizations - Manage and consolidate multiple AWS accounts
  6. S3
  7. SNS
  8. CloudWatch
  9. KMS
  10. AWS Systems Manager (SSM)
  11. AWS Config
  12. Amazon EC2 Image Builder - Service to automate the creation of EC2 AMIs
  13. AWS CloudFormation - Infrastructure as code service