EC2 Instance Storage

Question 1

EBS Volume

Answer 1

• An EBS (Elastic Block Store) Volume is a network drive you can attach to your instances while they run
• It allows your instances to persist data, even after their termination
• They can only be mounted to one instance at a time (at the CCP
  level)
• They are bound to a specific availability zone
• Analogy:Think of them as a “network USB stick”
• Free tier: 30 GB of free EBS storage of type General Purpose (SSD) or
  Magnetic per month

Question 2

What happens when terminating an EC2 instance with Root Volume type and other volume Type to store data?

Answer 2

Root volume will be deleted, as its “Delete on Termination” attribute is enabled by default. any other volume types will not be deleted as its “delete on termination” attribute is disabled by default.

Question 3

AMI

Answer 3

• AMI = Amazon Machine Image
• AMI are a customization of an EC2 instance
• You add your own software, configuration, operating system, monitoring… * Faster boot / configuration time because all your software is pre-packaged
• AMI are built for a specific region (and can be copied across regions). you can’t launch an EC2 instance using an AMI in another AWS region, but you can copy the ami to the target region and then use it to create your EC2 instance.
• You can launch EC2 instances from:
• A Public AMI: AWS provided
• Your own AMI: you make and maintain them yourself
• An AWS Marketplace AMI: an AMI someone else made (and potentially sells)

Question 4

EBS Volume Types

Answer 4

• gp2 / gp3 (SSD): General purpose SSD volume that balances price and performance for a wide variety of workloads. System boot volumes,Virtual desktops, Development and test environments. max IOPS 16K.
• io1 / io2 (SSD): Highest-performance SSD volume for mission-critical low-latency or high-throughput workloads. Great for databases workloads (sensitive to storage perf and consistency). Max PIOPS: 64,000 for Nitro EC2 instances & 32,000 for other.
• st1 (HDD): Low cost HDD volume designed for frequently accessed, throughput- intensive workloads. Big Data, Data Warehouses, Log Processing.
• sc1 (HDD): Lowest cost HDD volume designed for less frequently accessed workloads.

Question 5

EBS multi attach

Answer 5

Attach the same EBS volume to multiple EC2 instances in the same AZ
* Each instance has full read & write permissions to the high-performance volume
* Use case:
* Achieve higher application availability in clustered
Linux applications (ex:Teradata)
* Applications must manage concurrent write operations
* Up to 16 EC2 Instances at a time
* Must use a file system that’s cluster-aware (not
XFS, EXT4, etc…)

Question 6

How do you encrypt an unencrypted EBS volume attached to your EC2 instance?

Answer 6

Create an EBS snapshot of your EBS volume. copy the snapshot and click the option to encrypt the copied snapshot. use the encrypted snapshot to create a new EBS volume.

Question 7

EFS

Answer 7

• Elastic File System. Managed NFS (network file system) that can be mounted on many EC2
• EFS works with EC2 instances in multi-AZ
• Highly available, scalable, expensive (3x gp2), pay per use
• Mounting 100s of instances across AZ * EFS share website files (WordPress)
• Only for Linux Instances (POSIX)
• EFS has a higher price point than EBS * Can leverage EFS-IA for cost savings

Question 8

Instance Store

Answer 8

• EBS volumes are network drives with good but “limited” performance
• If you need a high-performance hardware disk, use EC2 Instance Store
• Better I/O performance
• EC2 Instance Store lose their storage if they’re stopped (ephemeral)
• Good for buffer / cache / scratch data / temporary content
• Risk of data loss if hardware fails
• Backups and Replication are your responsibility