Launch configurations
Important
You can not call CreateLaunchConfiguration with new Amazon EC2 instance types that are
released after December 31, 2022. In addition, any new accounts
created on or after June 1, 2023 will not have the option to create
new launch configurations through the console. In the future, new accounts will not be able to create
new launch configurations by using the console, API, CLI, and CloudFormation. Migrate to launch templates
to ensure that you don’t need to create new launch configurations now or in the future. For information
about migrating your Auto Scaling groups to launch templates, see
Migrate your Auto Scaling groups to launch
templates.
A launch configuration is an instance configuration template that an Auto Scaling group uses to launch EC2 instances. When you create a launch configuration, you specify information for the instances. Include the ID of the Amazon Machine Image (AMI), the instance type, a key pair, one or more security groups, and a block device mapping. If you've launched an EC2 instance before, you specified the same information in order to launch the instance.
You can specify your launch configuration with multiple Auto Scaling groups. However, you can only specify one launch configuration for an Auto Scaling group at a time, and you can't modify a launch configuration after you've created it. To change the launch configuration for an Auto Scaling group, you must create a launch configuration and then update your Auto Scaling group with it.