Basic CLI commands (s3, ec2) in AWS - Mini Project: Build & Apply

Basic AWS CLI Commands for S3 and EC2

📖 Scenario: You are starting to manage cloud resources using AWS CLI. You want to practice basic commands to list and create storage buckets and virtual servers.

🎯 Goal: Learn to use AWS CLI commands to list S3 buckets, create a new S3 bucket, list EC2 instances, and launch a new EC2 instance.

📋 What You'll Learn

Use AWS CLI commands exactly as specified

Create an S3 bucket with the exact name given

Launch an EC2 instance with the specified parameters

List existing S3 buckets and EC2 instances

💡 Why This Matters

🌍 Real World

Managing cloud storage and virtual servers is a daily task for cloud engineers and developers. Knowing basic AWS CLI commands helps automate and speed up these tasks.

💼 Career

Many cloud jobs require familiarity with AWS CLI to manage resources efficiently without using the web console.

1

List all existing S3 buckets

Write the AWS CLI command to list all S3 buckets using aws s3 ls.

AWS

# Type the command to list all S3 buckets
# Your code here

Hint

This command shows all your current S3 buckets.

2

Create a new S3 bucket

Write the AWS CLI command to create a new S3 bucket named my-unique-bucket-12345 using aws s3 mb s3://my-unique-bucket-12345.

AWS

aws s3 ls
# Type the command to create the S3 bucket named my-unique-bucket-12345
# Your code here

Hint

This command makes a new bucket with the exact name given.

3

List all EC2 instances

Write the AWS CLI command to list all EC2 instances using aws ec2 describe-instances.

AWS

aws s3 ls
aws s3 mb s3://my-unique-bucket-12345
# Type the command to list all EC2 instances
# Your code here

Hint

This command shows details of your EC2 virtual servers.

4

Launch a new EC2 instance

Write the AWS CLI command to launch a new EC2 instance with the following exact parameters: use the Amazon Linux 2 AMI ID ami-0abcdef1234567890, instance type t2.micro, and key pair name my-key-pair. Use aws ec2 run-instances --image-id ami-0abcdef1234567890 --count 1 --instance-type t2.micro --key-name my-key-pair.

AWS

aws s3 ls
aws s3 mb s3://my-unique-bucket-12345
aws ec2 describe-instances
# Type the command to launch the EC2 instance with the specified parameters
# Your code here

Hint

This command starts a new virtual server with the exact settings given.

Practice

1. Which AWS CLI command lists all buckets in Amazon S3?

easy

A. aws s3 list-buckets

B. aws ec2 ls

C. aws ec2 describe-buckets

D. aws s3 ls

Solution

1. Step 1: Understand the service for buckets

   Amazon S3 stores buckets, so the command must use aws s3.

2. Step 2: Identify the correct action to list buckets

   The ls action lists buckets in S3. So aws s3 ls lists all buckets.

3. Final Answer:

   aws s3 ls -> Option D

4. Quick Check:

   List buckets = aws s3 ls [OK]

Hint: Use 'aws s3 ls' to list buckets quickly [OK]

Common Mistakes:

• Confusing EC2 commands with S3 commands
• Using 'list-buckets' which is not a valid CLI action
• Trying to list buckets with 'aws ec2' commands

2. Which command correctly starts an EC2 instance with ID i-1234567890abcdef0?

easy

A. aws ec2 start-instances --instance-ids i-1234567890abcdef0

B. aws ec2 start-instance --instance-ids i-1234567890abcdef0

C. aws ec2 start-instances --instance-id i-1234567890abcdef0

D. aws ec2 start-instance --instance-id i-1234567890abcdef0

Solution

1. Step 1: Identify the correct EC2 start command

   The correct command to start instances is start-instances (plural).

2. Step 2: Use the correct option name for instance IDs

   The option is --instance-ids (plural), not --instance-id.

3. Final Answer:

   aws ec2 start-instances --instance-ids i-1234567890abcdef0 -> Option A

4. Quick Check:

   Start instances = start-instances + --instance-ids [OK]

Hint: Use plural 'start-instances' and '--instance-ids' options [OK]

Common Mistakes:

• Using singular 'start-instance' instead of 'start-instances'
• Using '--instance-id' instead of '--instance-ids'
• Mixing up EC2 and S3 commands

3. What is the output of this command if the bucket my-bucket contains two files file1.txt and file2.txt?

aws s3 ls s3://my-bucket/

medium

A. Lists the names and sizes of file1.txt and file2.txt

B. Shows an error: bucket not found

C. Lists only the bucket name my-bucket

D. Deletes the files in the bucket

Solution

1. Step 1: Understand the command purpose

   aws s3 ls s3://my-bucket/ lists objects inside the bucket my-bucket.

2. Step 2: Predict the output for files in the bucket

   The command will show the file names and their sizes for file1.txt and file2.txt.

3. Final Answer:

   Lists the names and sizes of file1.txt and file2.txt -> Option A

4. Quick Check:

   List bucket contents = file names + sizes [OK]

Hint: Use 'aws s3 ls s3://bucket/' to list files inside [OK]

Common Mistakes:

• Thinking it lists buckets instead of files
• Expecting deletion or error output
• Confusing bucket name listing with object listing

4. You run this command but get an error: aws ec2 describe-instances --instance-ids i-1234567890abcdef0. What is the likely cause?

medium

A. The command should be aws s3 describe-instances

B. The instance ID is incorrect or does not exist

C. You must use start-instances instead of describe-instances

D. You forgot to add --bucket option

Solution

1. Step 1: Check command correctness

   aws ec2 describe-instances --instance-ids is a valid command to get instance details.

2. Step 2: Identify common error reasons

   An error usually means the instance ID is wrong or the instance does not exist in your account or region.

3. Final Answer:

   The instance ID is incorrect or does not exist -> Option B

4. Quick Check:

   Invalid instance ID causes describe-instances error [OK]

Hint: Check instance ID spelling and region for describe-instances errors [OK]

Common Mistakes:

• Using S3 commands for EC2 tasks
• Confusing describe with start commands
• Adding irrelevant options like --bucket

5. You want to copy a local file photo.jpg to an S3 bucket my-photos in a folder 2024/. Which command correctly does this?

hard

A. aws ec2 cp photo.jpg s3://my-photos/2024/

B. aws s3 mv photo.jpg s3://my-photos/2024/

C. aws s3 cp photo.jpg s3://my-photos/2024/

D. aws s3 sync photo.jpg s3://my-photos/2024/

Solution

1. Step 1: Choose the correct AWS service and action

   Copying files to S3 uses aws s3 cp. EC2 commands do not handle S3 files.

2. Step 2: Use the correct source and destination syntax

   Source is local file photo.jpg, destination is S3 path s3://my-photos/2024/.

3. Final Answer:

   aws s3 cp photo.jpg s3://my-photos/2024/ -> Option C

4. Quick Check:

   Copy local file to S3 = aws s3 cp [OK]

Hint: Use 'aws s3 cp' to copy files to S3 buckets [OK]

Common Mistakes:

• Using 'mv' which moves instead of copies
• Using 'sync' for single file copy
• Using EC2 commands for S3 file operations