EC2 - AMI/Instance Store Flashcards
What does AMI stand for?
AMI stands for Amazon Machine Image.
What does an AMI represent?
An AMI represents a customization of an EC2 instance, including the software configuration, operating system, and other settings.
How does using a custom AMI benefit EC2 instance launch?
A custom AMI results in faster boot times and configuration times since the software is prepackaged and preinstalled.
Can you launch EC2 instances from different types of AMIs?
Yes, you can launch EC2 instances from public AMIs (provided by AWS), custom AMIs (created by you), or Marketplace AMIs (created and sold by others).
How do you create an AMI from an EC2 instance?
The process to create an AMI involves:
Launch an EC2 instance.
Customize the instance.
Stop the instance to ensure data integrity.
Build an AMI from the instance, which also creates EBS snapshots.
Can you copy an AMI across regions?
Yes, an AMI can be created in one region and then copied to other regions to leverage AWS’s global infrastructure.
What is the process for creating and launching instances from an AMI across Availability Zones?
Launch and customize an EC2 instance in one Availability Zone (e.g., US-EAST-1A).
Create an AMI from the instance.
Copy the AMI to another AZ (e.g., US-EAST-1B).
Launch a new EC2 instance from the AMI in the new AZ.
What is the AWS Marketplace AMI?
Marketplace AMIs are AMIs created by vendors and sold in the AWS Marketplace. These AMIs are often preconfigured with software and save users time in setup.
What is EC2 Instance Store?
EC2 Instance Store is a hardware disk directly attached to the physical server hosting the EC2 instance, providing high-performance storage.
Why would you use EC2 Instance Store?
EC2 Instance Store is ideal for high I/O performance and high throughput, making it a good choice for workloads that require fast disk access.
What is the main limitation of EC2 Instance Store?
The main limitation is that the storage is ephemeral, meaning if the EC2 instance is stopped or terminated, the data stored in the Instance Store is lost.
What are good use cases for EC2 Instance Store?
EC2 Instance Store is suitable for buffering, caching, scratch data, and temporary content, but not for long-term storage.
What happens if the underlying hardware for EC2 Instance Store fails?
If the underlying server hardware fails, you risk data loss since the Instance Store is directly tied to the physical server.
How is EC2 Instance Store different from EBS?
EBS provides persistent storage that survives instance stop/termination, whereas EC2 Instance Store is ephemeral and data is lost if the instance is stopped or terminated.
What responsibility do you have when using EC2 Instance Store?
You are responsible for backing up and replicating data stored in EC2 Instance Store, especially since it is ephemeral and could be lost if the instance fails.
