Explanation:

SSL certificates linked to an IP address.
Firewall rules that allow or deny traffic using IP address ranges.
DNS name resolution, where a change in the IP address would require updating host records.
Role-based VMs such as Domain Controllers and DNS servers.
IP address-based security models which require apps or services to have a static IP address.

Explanation:

Following is the command

aws cloudwatch set-alarm-state --alarm-name <Created alarm name> --state-reason <comment> --state-value ALARM

Explanation:

Following is the AWS CLI command

aws s3 presign <bucket URL> --expires-in <duration in seconds> --region <location name>

Example:

aws configure set default.s3.signature_version s3v4
aws s3 presign s3://xdk-bucket/xdkimage.jpg --expires-in 600 --region eu-east-1

Explanation:

Verify the logs at the following location to debug the instance launch
/var/log/cloud-init.log
/var/log/cfn-init.log

Explanation:

Following is the command to set the health status of the specified instance.

aws autoscaling set-instance-health --instance-id <ID> --health-status <Healthy/Unhealthy>

Example: To set the instance Unhealthy

aws autoscaling set-instance-health --instance-id i-123456789 --health-status Unhealthy