Amazon Machine Images (AMIs) in AWS - Step-by-Step Execution

Process Flow - Amazon Machine Images (AMIs)

Create AMI from EC2 Instance

↓

AMI Stored in S3-backed Storage

↓

Launch New EC2 Instance Using AMI

↓

New Instance Has Same OS and Software

↓

Modify or Update Instance

↓

Optionally Create New AMI from Updated Instance

This flow shows how you create an AMI from an EC2 instance, store it, launch new instances from it, and optionally update by creating new AMIs.

Execution Sample

AWS

1. Create AMI from running EC2 instance
2. AMI saved as image with OS and apps
3. Launch new EC2 instance using AMI
4. New instance boots with same setup

This sequence creates an AMI from an EC2 instance and launches a new instance with the same configuration.

Process Table

Step	Action	Input	Output	State Change
1	Create AMI	EC2 instance ID i-12345	AMI ami-abcde created	AMI stored with OS and apps snapshot
2	Store AMI	AMI ami-abcde	AMI available in AMI list	AMI ready for use
3	Launch EC2 instance	AMI ami-abcde	New instance i-67890 launched	New instance has same OS and apps as original
4	Instance running	Instance i-67890	Instance ready for use	Instance state: running
5	Modify instance	Instance i-67890	Instance updated	Instance software/config changed
6	Create new AMI	Updated instance i-67890	AMI ami-fghij created	New AMI with updated config stored
7	Exit	No further action	Process complete	AMI lifecycle demonstrated

💡 Process stops after new AMI creation or when no more instances are launched

Status Tracker

Variable	Start	After Step 1	After Step 3	After Step 5	Final
EC2 Instance ID	i-12345	i-12345	i-67890 (new)	i-67890 (updated)	i-67890 (updated)
AMI ID	none	ami-abcde	ami-abcde	ami-abcde	ami-fghij
Instance State	running	running	running	running	running

Key Moments - 3 Insights

Why does creating an AMI not affect the running EC2 instance?

Because creating an AMI takes a snapshot of the instance's disk without stopping or changing the running instance, as shown in step 1 and 4 of the execution_table.

What happens when you launch a new EC2 instance from an AMI?

A new instance is created with the exact OS and software setup as the AMI, demonstrated in step 3 and 4 where the new instance i-67890 boots with the same configuration.

How can you update an AMI after changing the instance?

You modify the running instance and then create a new AMI from it, as shown in steps 5 and 6 where the updated instance leads to a new AMI ami-fghij.

Visual Quiz - 3 Questions

Look at the execution_table, what is the AMI ID after step 1?

A ami-abcde

B ami-fghij

C none

D i-12345

💡 Hint

Check the 'AMI ID' variable in variable_tracker after Step 1

At which step does the new EC2 instance get launched?

A Step 2

B Step 5

C Step 3

D Step 6

💡 Hint

Look at the 'Action' column in execution_table for launching instance

If you modify the instance but do not create a new AMI, what happens to the AMI ID?

A It changes to a new ID

B It remains the same

C It gets deleted

D It becomes unavailable

💡 Hint

Refer to variable_tracker showing AMI ID after Step 5 before new AMI creation

Concept Snapshot

Amazon Machine Images (AMIs) are snapshots of EC2 instances.
They store OS and software configuration.
You create an AMI from a running instance without stopping it.
Launch new instances using AMIs to replicate setups.
Update instances and create new AMIs to save changes.

Full Transcript

Amazon Machine Images (AMIs) let you save the exact setup of an EC2 instance including its operating system and installed software. You start by creating an AMI from a running EC2 instance, which takes a snapshot without stopping the instance. This AMI is stored and can be used to launch new EC2 instances that have the same configuration as the original. If you update the software or settings on an instance, you can create a new AMI from it to save those changes. This process helps you quickly replicate or scale your environment with consistent setups.

Practice

1. What is the main purpose of an Amazon Machine Image (AMI)?

easy

A. To monitor server performance

B. To store user data in the cloud

C. To save a server setup so it can be reused later

D. To manage network traffic

Solution

1. Step 1: Understand what an AMI represents

   An AMI is a snapshot of a server's setup including its software and settings.

2. Step 2: Identify the main use of AMIs

   AMIs allow you to reuse this saved setup to launch new servers quickly.

3. Final Answer:

   To save a server setup so it can be reused later -> Option C

4. Quick Check:

   AMI = reusable server setup [OK]

Hint: AMI saves server setup for reuse [OK]

Common Mistakes:

• Confusing AMI with data storage
• Thinking AMI monitors performance
• Assuming AMI manages network

2. Which AWS CLI command correctly creates an AMI from a running instance with ID i-1234567890abcdef0?

easy

A. aws ec2 start-image --instance i-1234567890abcdef0 --name MyServerImage

B. aws ec2 launch-image --instance-id i-1234567890abcdef0 --name MyServerImage

C. aws ec2 make-ami --id i-1234567890abcdef0 --image-name MyServerImage

D. aws ec2 create-image --instance-id i-1234567890abcdef0 --name MyServerImage

Solution

1. Step 1: Identify the correct AWS CLI command for creating an AMI

   The correct command is aws ec2 create-image with the instance ID and a name.

2. Step 2: Match the command syntax with the options

   aws ec2 create-image --instance-id i-1234567890abcdef0 --name MyServerImage uses the correct command and parameters.

3. Final Answer:

   aws ec2 create-image --instance-id i-1234567890abcdef0 --name MyServerImage -> Option D

4. Quick Check:

   create-image + instance-id = create AMI [OK]

Hint: Use 'create-image' with instance ID to make AMI [OK]

Common Mistakes:

• Using wrong command like start-image or launch-image
• Mixing up parameter names
• Omitting instance ID

3. You run this AWS CLI command:
aws ec2 create-image --instance-id i-0abc123def456 --name TestImage
What will be the immediate result?

medium

A. An AMI creation request is started; image becomes available after processing

B. The instance is stopped and then an AMI is created

C. A new AMI is created and available instantly

D. The command fails because instance ID is invalid

Solution

1. Step 1: Understand the behavior of create-image command

   The command starts the AMI creation process but the image is not instantly ready.

2. Step 2: Identify the correct immediate result

   The AMI creation runs in background; the image becomes available after some time.

3. Final Answer:

   An AMI creation request is started; image becomes available after processing -> Option A

4. Quick Check:

   AMI creation is asynchronous [OK]

Hint: AMI creation takes time; not instant [OK]

Common Mistakes:

• Assuming AMI is ready immediately
• Thinking instance stops automatically
• Believing command fails without error

4. You tried to create an AMI with this command:
aws ec2 create-image --instance i-0abc123def456 --name MyImage
But it failed. What is the error?

medium

A. Instance ID format is incorrect

B. Missing required parameter --instance-id

C. AMI name is invalid

D. You cannot create AMI from a running instance

Solution

1. Step 1: Check the command parameters

   The command uses --instance instead of the required --instance-id parameter.

2. Step 2: Identify the cause of failure

   The AWS CLI expects --instance-id to specify the instance; missing this causes failure.

3. Final Answer:

   Missing required parameter --instance-id -> Option B

4. Quick Check:

   Use --instance-id to specify instance [OK]

Hint: Use --instance-id, not --instance [OK]

Common Mistakes:

• Using wrong parameter name
• Assuming instance ID format error
• Thinking AMI can't be made from running instance

5. You want to launch multiple identical servers quickly using an AMI. Which steps should you follow?

hard

A. Create an AMI from a configured instance, then launch new instances using that AMI

B. Launch new instances, then manually configure each one separately

C. Create snapshots of volumes, then attach them to new instances

D. Use AWS Lambda to copy instance settings to new servers

Solution

1. Step 1: Understand how to reuse server setups

   Creating an AMI from a configured instance saves its setup for reuse.

2. Step 2: Use the AMI to launch new instances

   Launching new servers from the AMI ensures they have the same software and settings quickly.

3. Final Answer:

   Create an AMI from a configured instance, then launch new instances using that AMI -> Option A

4. Quick Check:

   AMI enables fast identical server launches [OK]

Hint: Create AMI first, then launch servers from it [OK]

Common Mistakes:

• Configuring each server manually
• Using snapshots instead of AMIs for full setup
• Thinking AWS Lambda copies server setups