Troubleshooting AWS Autoscaling

Exam Question Scenario
Autoscaling configuration fails to launch EC2 instances
Description
The following are required for autoscaling configuration:
Configuration for autoscaling launch that allows you to choose anAMI
Type of instance
IAM role (optional).
Security group
Key pair file
Autoscaling group configuration allows you to select AZ to be used to launch the EC2 instances with the selected launch configurationTroubleshooting key points :-
The AMI ID is not yet available or is pending, and cannot be used for instance launch.
The launch configuration does not include a security group.
The key pair associated with the EC2 instance is not present
The Autoscaling Group was not found or is incorrectly configured
AZ configured with the Autoscaling Group is no longer supported. It might not be possible to get it.
Invalid EBS block device mappings
The AZ does not support instances types
Capacity limits are reached due to the limitation on the number or type of instance types that can be launched in a particular region, or because AWS is unable to provision the specified instance type within the AZ (e.g. no more spot instances or On-demand instances availability)References
More details @ AWS Autoscaling Developer Guide