Basic CLI commands (s3, ec2) in AWS - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

Understanding AWS S3 Bucket Creation Behavior

You run the command aws s3 mb s3://my-unique-bucket-12345. What is the expected result if the bucket name is globally unique and you have permissions?

AWS

aws s3 mb s3://my-unique-bucket-12345

A The bucket is created and a success message is shown.

B The command lists all existing buckets instead of creating one.

C The command fails with an error about invalid bucket name.

D The command creates a folder inside an existing bucket.

💡 Hint

Think about what mb means in the AWS S3 CLI.

The aws s3 mb command means 'make bucket'. If the bucket name is unique and you have permission, it creates the bucket and shows a success message.

❓ Configuration

intermediate

Correct AWS CLI Command to List EC2 Instances

Which AWS CLI command correctly lists all EC2 instances in the default region?

A aws ec2 get-instances

B aws ec2 list-instances

C aws ec2 show-instances

D aws ec2 describe-instances

💡 Hint

Think about the AWS CLI command that describes resources.

The correct command to list EC2 instances is aws ec2 describe-instances. Other options are invalid commands.

❓ Architecture

advanced

Choosing the Right AWS CLI Command for EC2 Instance State Change

You want to stop an EC2 instance with ID i-0abcd1234efgh5678 using AWS CLI. Which command will correctly stop the instance?

A aws ec2 stop-instances --instance-ids i-0abcd1234efgh5678

B aws ec2 start-instances --instance-ids i-0abcd1234efgh5678

C aws ec2 reboot-instances --instance-ids i-0abcd1234efgh5678

D aws ec2 terminate-instances --instance-ids i-0abcd1234efgh5678

💡 Hint

Stopping an instance is different from terminating or rebooting it.

The stop-instances command stops the instance without deleting it. Terminate deletes it, reboot restarts it, and start turns it on.

❓ security

advanced

AWS CLI Command Impact on S3 Bucket Permissions

You run aws s3 cp file.txt s3://mybucket/ without specifying any ACL options. What is the default permission behavior for the uploaded file?

AWS

aws s3 cp file.txt s3://mybucket/

A The file is uploaded with public read permissions.

B The file is uploaded with private permissions, accessible only to the bucket owner.

C The file is uploaded with permissions inherited from the bucket policy.

D The upload fails due to missing ACL specification.

💡 Hint

Think about default ACL behavior when none is specified.

By default, files uploaded to S3 are private and accessible only to the bucket owner unless ACL options are specified.

✅ Best Practice

expert

Best Practice for AWS CLI EC2 Instance Tagging During Launch

You want to launch an EC2 instance and tag it with Environment=Production using a single AWS CLI command. Which command correctly achieves this?

A aws ec2 run-instances --image-id ami-12345678 --count 1 --instance-type t2.micro --tag Key=Environment Value=Production

B aws ec2 run-instances --image-id ami-12345678 --count 1 --instance-type t2.micro --tags Key=Environment,Value=Production

C aws ec2 run-instances --image-id ami-12345678 --count 1 --instance-type t2.micro --tag-specifications 'ResourceType=instance,Tags=[{Key=Environment,Value=Production}]'

D aws ec2 run-instances --image-id ami-12345678 --count 1 --instance-type t2.micro --tag-specifications 'Tags=[{Key=Environment,Value=Production}]'

💡 Hint

Tagging requires specifying resource type and tags in a specific format.

The --tag-specifications option requires the resource type and tags in JSON-like syntax. Only option C uses the correct syntax.