3.2 Ensure each Auto-Scaling Group is configured for multiple Availability Zones


Auto Scaling helps maintain application availability and allows you to scale your Amazon EC2 capacity up or down automatically according to conditions you define.

You can use Auto Scaling to help ensure that you are running your desired number of Amazon EC2 instances or can automatically increase the number of Amazon EC2 instances during demand spikes to maintain performance and decrease capacity during lulls to reduce costs.

These properties can be defined within the Auto-Scaling Group configuration.
Ensures high availability of the application and web tiers in the event of a host or Availability Zone failure.


Using the Amazon Unified CLI:

* List all the subnets and the associated Availability Zones from the application VPC:

aws ec2 describe-subnets --query "Subnets[?VpcId == '_<application_vpc>_'].{VPC:VpcId, Subnet:SubnetId, AZ:AvailabilityZone, CIDR:CidrBlock}"

* Update AutoScaling Group to include more than 1 Availability Zones within the same VPC:

aws autoscaling update-auto-scaling-group --auto-scaling-group-name _<autoscaling_group_name>_ --availability-zones _<application_az>_

See Also


Item Details


References: 800-53|SI-13(5)

Plugin: amazon_aws

Control ID: 6461abab658c066e6abed0b64f14ea3a1072df2a2c08740d2437e5565033a008