EC2 Instance Storage

EBS

• network drive you can attach to your instances while they run
• allow instances to persist data, even after termination
• bound to a specific AZ (not region). It is possible to migrate them between different AZs using EBS Snapshots.
• 비유 : network USB stick
• delete on termination : Root volume type은 yes가 default. Any other volume types는 no가 default
• attached to 1 instance at a time (except multi-attach io1/io2)

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EBS Snapshot

• make a backup of your EBS volume at a point in time
• copy snapshots across AZ or region
• Create volume from snapshot : target AZ doesn't have to remain original AZ

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AMI (Amazon Machine Image)

• customization of an EC2 instance
  • add own software, configuration, OS, monitoring...
  • faster boot / configuration time because all your software is pre-packed
• built for a specific region but can be copied across regions

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EC2 Instance Store

• high-performance hardware disk (hardware attached volume)
• better I/O performance
• lose their storage if they're stopped
• good for buffer / cache / scratch data / temporary content

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EBS Volume Types

• only gp2/gp3 and io1/io2 Block Express can be used as boot volumes (where the root OS is going to be running)

gp2/gp3

• cost effective low-latency storage
• gp3 : independently set the IOPS and the throughput
• gp2 : IOPS and the throughput linked together

io1/io2 Block Express

• Provisioned IOPS
• databases workloads
• EBS multi-attach
  • attach the same EBS volume to multiple EC2 instances in the same AZ
  • up to 16 EC2 instances at a time

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EBS Encryption

• leverages keys from KMS
• 1. unencrypted EBS volume 생성
• 2. unencrypted snapshot 생성
• 3. encrypted snapshot 복사
• 4. encrypted snapshot으로부터 encrypted EBS volumne 생성

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EFS (Elastic File System)

• Managed NFS (Network File System) that can be mounted on many EC2
• EC2 instances in multi-AZ all connect at the same time to the same network file system through EFS
• Compatible with Linux based AMI (not Windows)
• Bursting : have the throguhput scale with the amount of storage and going a little bit over
• Elastic : regardless of the size of storage, will give you all the I/O you need, and will scale automatically, and only pay for what you use
• Provisioned : know in advance the throughput you're going to be needing