Why EC2 matters for compute in AWS - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to launch an EC2 instance using AWS CLI.

AWS

aws ec2 run-instances --image-id [1] --count 1 --instance-type t2.micro

Drag options to blanks, or click blank then click option'

Aus-east-1

Binstance-12345

Ct2.large

Dami-0abcdef1234567890

Attempts:

3 left

💡 Hint

Common Mistakes

Using instance type or region instead of image ID.

Providing an invalid or incomplete AMI ID.

The --image-id option requires a valid AMI ID like ami-0abcdef1234567890 to launch an EC2 instance.

2fill in blank

medium

Complete the code to specify the instance type when launching an EC2 instance.

AWS

aws ec2 run-instances --image-id ami-0abcdef1234567890 --count 1 --instance-type [1]

Drag options to blanks, or click blank then click option'

At2.micro

Bmy-key-pair

Cus-west-2

Dami-123456

Attempts:

3 left

💡 Hint

Common Mistakes

Using an AMI ID or region instead of instance type.

Using a key pair name in place of instance type.

The --instance-type option defines the hardware configuration. t2.micro is a common small instance type.

3fill in blank

hard

Fix the error in the command to add a key pair for SSH access.

AWS

aws ec2 run-instances --image-id ami-0abcdef1234567890 --count 1 --instance-type t2.micro --key-name [1]

Drag options to blanks, or click blank then click option'

At2.micro

Bus-east-1

Cmy-key-pair

Dami-0abcdef1234567890

Attempts:

3 left

💡 Hint

Common Mistakes

Using region or instance type instead of key pair name.

Using an AMI ID as the key name.

The --key-name option requires the name of an existing key pair like my-key-pair to enable SSH access.

4fill in blank

hard

Fill both blanks to create a security group rule allowing SSH access on port 22.

AWS

aws ec2 authorize-security-group-ingress --group-id [1] --protocol [2] --port 22 --cidr 0.0.0.0/0

Drag options to blanks, or click blank then click option'

Asg-0123456789abcdef0

Btcp

Cudp

Dsg-abcdef0123456789

Attempts:

3 left

💡 Hint

Common Mistakes

Using UDP protocol for SSH.

Using incorrect security group IDs.

The --group-id specifies the security group ID like sg-0123456789abcdef0. The --protocol for SSH is tcp.

5fill in blank

hard

Fill all three blanks to tag an EC2 instance with Name and Environment tags.

AWS

aws ec2 create-tags --resources [1] --tags Key=Name,Value=[2] Key=Environment,Value=[3]

Drag options to blanks, or click blank then click option'

Ai-0abcdef1234567890

BProduction

CWebServer

DDevelopment

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up tag values.

Using incorrect instance IDs.

The --resources option needs the instance ID like i-0abcdef1234567890. The Name tag is set to WebServer and the Environment tag to Production.

Practice

1. What is the main benefit of using Amazon EC2 for computing tasks?

easy

A. It automatically writes code for your applications.

B. It stores large amounts of data permanently.

C. It manages your email communications.

D. It provides virtual servers that you can start and stop anytime.

Solution

1. Step 1: Understand EC2's purpose

   EC2 offers virtual computers (servers) in the cloud that you can control.

2. Step 2: Identify the key feature

   You can launch, stop, and scale these virtual servers anytime as needed.

3. Final Answer:

   It provides virtual servers that you can start and stop anytime. -> Option D

4. Quick Check:

   EC2 = virtual servers you control [OK]

Hint: EC2 = virtual computers you can manage anytime [OK]

Common Mistakes:

• Confusing EC2 with storage services
• Thinking EC2 writes code automatically
• Mixing EC2 with email or messaging services

2. Which of the following is the correct way to describe an EC2 instance?

easy

A. A virtual server you can launch in the cloud.

B. A database service for storing records.

C. A software tool for editing documents.

D. A physical server you buy and install in your office.

Solution

1. Step 1: Define EC2 instance

   An EC2 instance is a virtual server running in the cloud, not a physical machine.

2. Step 2: Match description

   A virtual server you can launch in the cloud. correctly states it is a virtual server you can launch anytime.

3. Final Answer:

   A virtual server you can launch in the cloud. -> Option A

4. Quick Check:

   EC2 instance = virtual cloud server [OK]

Hint: EC2 instance = virtual server, not physical [OK]

Common Mistakes:

• Thinking EC2 is a physical server
• Confusing EC2 with software tools
• Mixing EC2 with database services

3. Consider this scenario: You launch an EC2 instance, run a compute-heavy task, then stop the instance. What happens to the compute power and billing?

medium

A. Compute power stops and billing stops when the instance is stopped.

B. Compute power continues but billing stops when the instance is stopped.

C. Compute power stops but billing continues when the instance is stopped.

D. Compute power and billing continue even if the instance is stopped.

Solution

1. Step 1: Understand EC2 instance stop behavior

   When you stop an EC2 instance, the virtual server stops running, so compute power is no longer used.

2. Step 2: Understand billing during stop

   Billing for compute stops because you are not using the server, though storage may still be billed separately.

3. Final Answer:

   Compute power stops and billing stops when the instance is stopped. -> Option A

4. Quick Check:

   Stopped instance = no compute, no billing [OK]

Hint: Stop instance = stop compute and billing [OK]

Common Mistakes:

• Assuming billing continues after stopping
• Thinking compute runs when stopped
• Confusing storage billing with compute billing

4. You tried to launch an EC2 instance but got an error saying your account has reached the instance limit. What should you do to fix this?

medium

A. Change the instance type to a larger size.

B. Delete your AWS account and create a new one.

C. Request a limit increase from AWS support.

D. Restart your computer and try again.

Solution

1. Step 1: Identify the cause of the error

   A limit error means your AWS account has a maximum number of instances allowed, which you reached.

2. Step 2: Find the correct fix

   You can request AWS to increase this limit by contacting support, which is the proper solution.

3. Final Answer:

   Request a limit increase from AWS support. -> Option C

4. Quick Check:

   Instance limit error = request increase [OK]

Hint: Limit errors need AWS support request [OK]

Common Mistakes:

• Deleting account unnecessarily
• Changing instance size won't fix limits
• Restarting computer does not affect AWS limits

5. You want to run a web application that needs to handle sudden traffic spikes without delay. How does EC2 help you achieve this?

hard

A. By automatically writing code to optimize your app.

B. By letting you quickly launch more instances to add compute power as needed.

C. By storing all your data in a single large server.

D. By sending emails to users when traffic spikes.

Solution

1. Step 1: Understand traffic spikes and compute needs

   Sudden traffic spikes require more computing power to handle extra users smoothly.

2. Step 2: How EC2 supports scaling

   EC2 allows you to launch more virtual servers quickly, adding compute power to meet demand.

3. Final Answer:

   By letting you quickly launch more instances to add compute power as needed. -> Option B

4. Quick Check:

   EC2 enables fast scaling for traffic spikes [OK]

Hint: EC2 lets you add servers fast for traffic spikes [OK]

Common Mistakes:

• Thinking EC2 writes code automatically
• Confusing compute scaling with data storage
• Assuming EC2 manages emails for traffic