imageId

The ID of the AMI or a Systems Manager parameter. The Systems Manager parameter will resolve to the ID of the AMI at instance launch.

The value depends on what you specified in the request. The possible values are:

• If an AMI ID was specified in the request, then this is the AMI ID.

• If a Systems Manager parameter was specified in the request, and ResolveAlias was configured as true, then this is the AMI ID that the parameter is mapped to in the Parameter Store.

• If a Systems Manager parameter was specified in the request, and ResolveAlias was configured as false, then this is the parameter value.

For more information, see Use a Systems Manager parameter instead of an AMI ID in the Amazon EC2 User Guide.