AWS Getting Started - Planning for High Availability (HA)

For those looking to create a highly available deployment, the following considerations can be key to your deployment. 

Amazon EC2 allows placement of instances in multiple locations. Your instance can be placed in a region, which corresponds roughly to a physical location or area, such as US East (N. Virginia), Canada (Central), EU (Ireland), and so forth. There are numerous options to choose from. Alternatively, it can be placed in an Availability Zone, which is essentially a logical grouping of servers or racks of servers separated into an artificial ‘location’ within a given region. Instances paired across Availability Zones are isolated from failures in other Zones, ensuring redundancy in case of large-scale failures.

For more information on Regions and Availability Zones, go to:

    • AWS Documentation: Regions and Availability Zones 

      Amazon EC2 is hosted in multiple locations world-wide. These locations are composed of Regions, Availability Zones, Local Zones, AWS Outposts, and Wavelength Zones. Each Region is a separate geographic area.

      • Availability Zones are multiple, isolated locations within each Region.

      • Local Zones provide you the ability to place resources, such as compute and storage, in multiple locations closer to your end users.

      • AWS Outposts brings native AWS services, infrastructure, and operating models to virtually any data center, co-location space, or on-premises facility.

      • Wavelength Zones allow developers to build applications that deliver ultra-low latencies to 5G devices and end users. Wavelength deploys standard AWS compute and storage services to the edge of telecommunication carriers' 5G networks.

      AWS operates state-of-the-art, highly available data centers. Although rare, failures can occur that affect the availability of instances that are in the same location. If you host all of your instances in a single location that is affected by a failure, none of your instances would be available.