AWS Compute & Storage

How Compute & Storage Fit Together

EC2 — Elastic Compute Cloud

EC2 gives you virtual servers (called instances) that you can configure with any OS, CPU, memory, and storage combination. It's the most fundamental AWS compute service.

Instance Types

Launching an EC2 Instance

# Launch a t3.micro instance with Amazon Linux 2023
aws ec2 run-instances \
  --image-id ami-0c02fb55956c7d316 \
  --instance-type t3.micro \
  --key-name my-key-pair \
  --security-group-ids sg-0123456789abcdef0 \
  --subnet-id subnet-0123456789abcdef0 \
  --tag-specifications 'ResourceType=instance,Tags=[{Key=Name,Value=my-server}]'

# Check running instances
aws ec2 describe-instances \
  --filters "Name=instance-state-name,Values=running" \
  --query "Reservations[].Instances[].[InstanceId,InstanceType,PublicIpAddress]" \
  --output table

# Stop (preserves data) vs Terminate (deletes everything)
aws ec2 stop-instances --instance-ids i-0abc123def456
aws ec2 terminate-instances --instance-ids i-0abc123def456

S3 — Simple Storage Service

S3 stores objects (files up to 5 TB each) in buckets (containers). It's designed for 99.999999999% (11 nines) durability — your data essentially never gets lost.

Storage Classes

# Create a bucket
aws s3 mb s3://my-unique-bucket-name-2026

# Upload a file
aws s3 cp ./report.csv s3://my-unique-bucket-name-2026/data/

# Sync a local directory to S3
aws s3 sync ./build/ s3://my-unique-bucket-name-2026/ --delete

# List objects
aws s3 ls s3://my-unique-bucket-name-2026/data/ --recursive

# Enable versioning (protect against accidental deletes)
aws s3api put-bucket-versioning --bucket my-unique-bucket-name-2026 \
  --versioning-configuration Status=Enabled

Lambda — Serverless Compute

Lambda runs your code in response to events without provisioning servers. You upload a function, define a trigger (API Gateway, S3 upload, schedule), and AWS handles everything else — scaling, patching, and availability.

Lambda vs. EC2

# Create a Lambda function (Python)
aws lambda create-function \
  --function-name processUpload \
  --runtime python3.12 \
  --handler lambda_function.lambda_handler \
  --role arn:aws:iam::123456789012:role/lambda-s3-role \
  --zip-file fileb://function.zip

# Invoke it manually
aws lambda invoke --function-name processUpload \
  --payload '{"key": "data/report.csv"}' output.json

# View logs
aws logs tail /aws/lambda/processUpload --follow

EBS — Elastic Block Store

EBS provides persistent block storage for EC2 instances — think of it as a virtual hard drive. Unlike instance store (which dies when the instance stops), EBS volumes persist independently.

# Create a 100 GB gp3 volume
aws ec2 create-volume --volume-type gp3 --size 100 \
  --availability-zone us-east-1a

# Attach to an EC2 instance
aws ec2 attach-volume --volume-id vol-0123456789abcdef0 \
  --instance-id i-0abc123def456 --device /dev/xvdf

# Create a snapshot (backup)
aws ec2 create-snapshot --volume-id vol-0123456789abcdef0 \
  --description "Daily backup"

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