EC2

Amazon Elastic Compute Cloud (EC2) provides resizable virtual servers with a wide range of instance types, pricing models, storage, and networking configurations.

Instance Types

EC2 instance types are grouped by family based on the target workload:

Family	Purpose	Example
t3/t4g	General purpose, burstable	Web servers, dev environments
m6i/m7g	General purpose, balanced	Application servers, databases
c6i/c7g	Compute optimized	Batch processing, ML inference
r6i/r7g	Memory optimized	In-memory caches, large databases
i4i	Storage optimized	High I/O databases
p4d/p5	GPU accelerated	ML training, HPC
g5	Graphics intensive	Video encoding, game streaming

Instance naming convention: <family><generation><attributes>.<size> (e.g., m6i.xlarge, c7g.2xlarge)

Pricing Models

• On-Demand: Pay by the second with no commitment
• Reserved Instances: 1 or 3-year commitment for up to 72% discount
• Savings Plans: Flexible pricing with commitment to usage amount ($/hr)
• Spot Instances: Up to 90% discount for interruptible workloads
• Dedicated Hosts: Physical server dedicated to your account for compliance requirements

CLI

AMI

# List the latest Amazon Linux 2023 AMI
aws ec2 describe-images \
  --owners amazon \
  --filters "Name=name,Values=al2023-ami-*-x86_64" \
  --query 'Images | sort_by(@, &CreationDate) | [-1].ImageId' \
  --output text

Run Instances

aws ec2 run-instances \
  --image-id ami-0abcdef1234567890 \
  --instance-type t3.medium \
  --key-name my-keypair \
  --security-group-ids sg-0123456789abcdef0 \
  --subnet-id subnet-0123456789abcdef0 \
  --tag-specifications 'ResourceType=instance,Tags=[{Key=Name,Value=my-server}]'

User Data

aws ec2 run-instances \
  --image-id ami-0abcdef1234567890 \
  --instance-type t3.micro \
  --user-data file://init-script.sh

Example init-script.sh:

#!/bin/bash
yum update -y
yum install -y httpd
systemctl enable --now httpd
echo "Hello from $(hostname)" > /var/www/html/index.html

Instance Lifecycle

# List instances
aws ec2 describe-instances \
  --filters "Name=tag:Name,Values=my-server" \
  --query 'Reservations[].Instances[].[InstanceId,State.Name,PublicIpAddress]' \
  --output table

# Stop / Start / Terminate
aws ec2 stop-instances --instance-ids i-0123456789abcdef0
aws ec2 start-instances --instance-ids i-0123456789abcdef0
aws ec2 terminate-instances --instance-ids i-0123456789abcdef0

# Reboot
aws ec2 reboot-instances --instance-ids i-0123456789abcdef0

# Get console output
aws ec2 get-console-output --instance-id i-0123456789abcdef0 --output text

Key Pairs

aws ec2 create-key-pair --key-name my-keypair --query 'KeyMaterial' --output text > my-keypair.pem
chmod 400 my-keypair.pem
aws ec2 describe-key-pairs
aws ec2 delete-key-pair --key-name my-keypair

EBS Volumes

# Create a volume
aws ec2 create-volume \
  --volume-type gp3 \
  --size 100 \
  --availability-zone us-east-1a \
  --tag-specifications 'ResourceType=volume,Tags=[{Key=Name,Value=data-vol}]'

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

# Detach
aws ec2 detach-volume --volume-id vol-0123456789abcdef0

# Resize (after expanding console)
aws ec2 modify-volume --volume-id vol-0123456789abcdef0 --size 200

# Snapshots
aws ec2 create-snapshot --volume-id vol-0123456789abcdef0 --description "weekly backup"
aws ec2 describe-snapshots --owner-ids self
aws ec2 delete-snapshot --snapshot-id snap-0123456789abcdef0

Reference:

1. Official Website
2. CentOS AWS AMIs