• Contents:

Intro on EBS from Cantrill’s SAA-C03

Elastic Block Store (EBS) Architecture

EBS Elastic Volumes

Ref: https://www.udemy.com/course/aws-certified-machine-learning-engineer-associate-mla-c01/learn/lecture/45284791

• 🔧 Allow changing volume seamlessly, without downtime nor the need to detach volume or restart its EC2 instance!
  • 💡 Kinda magic!
  • Most volumes support this nowadays, enabled by default
  • Just go to Actions → Modify Volume from the console
• Possible changes:
  • Increase volume size
    • ‼️ You can only increase, not decrease!
  • Change volume type
    • e.g. GP2 → GP3
    • Specify desired IOPS or throughput (or it will guess)
  • Adjust performance
    • Increase or decrease

Intro on EFS from Cantrill’s SAA-C03

Elastic File System (EFS)

Comparing EBS vs EFS

Ref: https://www.udemy.com/course/aws-certified-machine-learning-engineer-associate-mla-c01/learn/lecture/45356679

• EBS volumes:
  • Generally attached to one EC2 instance (except multi-attach io1/io2)
  • Locked at the AZ level
  • gp2: IO increases if disk size increases
  • gp3 & io1: can increase IO independently
  • Migrating EBS volume across AZ requires taking & restoring snapshot
    • EBS snapshots use IO → don't run them while app is handling a lot of traffic
  • Root EBS volumes of EC2 instances get terminated by default if instance gets terminated
    • Behavior can be changed
  • EBS Diagram
• EFS file systems:
  • Can be mounted in 100s of EC2 instances across AZs
  • With EFS, EC2 instances can share website files (e.g. WordPress)
  • Only for Linux Instances (POSIX)!
  • Can leverage Storage Tiers for cost savings
  • Generally more expensive than EBS
  • EFS Diagram