Describes the ID format settings for the root user and all IAM rolesand IAM users that have explicitly specified a longer ID (17-characterID) preference.Show details from next link. https://docs.aws.amazon.com/ja_jp/cli/latest/reference/ec2/describe-principal-id-format.html
aws ec2 describe-principal-id-format --region region |
| Resource IDs - Amazon Elastic Compute Cloud : http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/resource-ids.html |