AWS Instance Launch Issues

Invalid Device Name

Description: This error occurs when launching an EC2 instance due to an invalid device name assigned to one or more volumes.

Cause:

• The device name may already be used by the selected AMI.
• The name might be reserved for root volumes.
• A duplicate device name may be assigned to multiple volumes in the request.
• The specified device name might not be compatible with the OS.

Solution:

• Verify that the selected AMI does not already use the specified device name by running:
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aws ec2 describe-images --image-id ami_id --query 'Images[*].BlockDeviceMappings[].DeviceName'

• Avoid using names reserved for root volumes. Refer to AWS documentation for available device names.
• Ensure each volume in the request has a unique device name.
• Confirm that the specified device name follows the correct format for the operating system.

Instance Limit Exceeded

Description: You have reached the maximum number of instances allowed for your AWS account.

Cause: AWS sets limits on the number of instances per region based on account type.

Solution:

• Check your current instance limit using:
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aws ec2 describe-account-attributes --attribute-names max-instances

• Request a limit increase through the AWS Support Center.
• Terminate any unused instances to free up capacity.

Insufficient Instance Capacity

Description: AWS does not currently have enough available capacity for your requested instance type.

Cause: The selected instance type may have limited availability in the chosen region or AZ.

Solution:

• Try launching the instance in a different Availability Zone.
• Choose a different instance type with similar specifications.
• Check AWS Service Health Dashboard for regional capacity updates.

Requested Configuration Not Supported

Description: The selected instance type, AMI, or other configurations may not be supported.

Cause: Some instance types are only available in specific regions or with certain AMIs.

Solution:

• Check the AWS instance type availability in your region.
• Ensure that the AMI you are using supports the selected instance type.
• Refer to the AWS documentation for supported configurations.

Instance Terminates Immediately

Description: The EC2 instance shuts down as soon as it starts.

Cause:

• The root volume may be misconfigured or corrupted.
• The AMI used might be incompatible or faulty.
• Startup scripts might be causing an unexpected shutdown.

Solution:

• Check instance status in EC2 console or CloudWatch logs.
• Ensure the AMI is correctly configured and compatible.
• Review user data scripts to identify potential shutdown triggers.

Insufficient Permissions

Description: The user attempting to launch the instance does not have the required IAM permissions.

Cause:

• The IAM role lacks required EC2 instance launch permissions.
• Security policies may restrict instance creation.

Solution:

• Check IAM permissions for EC2 instance creation:
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aws iam get-user-policy --user-name your-username --policy-name policy-name

• Ensure the IAM role has "ec2:RunInstances" permission.
• Update policies or request elevated permissions from the administrator.

High CPU Usage After Windows Instance Starts

Description: Windows EC2 instances experience unusually high CPU usage immediately after boot.

Cause:

• Windows updates or background services consuming excessive resources.
• Misconfigured startup scripts or scheduled tasks.

Solution:

• Use Performance Monitor to check for resource-intensive processes.
• Disable unnecessary startup services and scheduled tasks.
• Ensure the instance has sufficient CPU and memory allocation.