02 - EC2 Fundamentals

EC2 Fundamentals - Overview

awsec2saa-c03index

Course Section Summary

This section covers Amazon EC2 (Elastic Compute Cloud), AWS's core compute service.

Study Files

# Topic File Priority
1 AWS Budget Setup 01-AWS-Budget-Setup 🟡 Setup
2 EC2 Basics & Instance Launch 02-EC2-Basics-Instance-Launch 🔴 High
3 EC2 Instance Types 03-EC2-Instance-Types 🔴 High
4 Security Groups 04-Security-Groups 🔴 High
5 SSH Access Methods 05-SSH-Access-Methods 🟡 Medium
6 IAM Roles for EC2 06-IAM-Roles-for-EC2 🔴 High
7 EC2 Purchasing Options 07-EC2-Purchasing-Options 🔴 High
8 IPv4 Charges & Spot Deep Dive 08-IPv4-Charges-Spot-Deep-Dive 🔴 High

Key Exam Topics

Must Know for SAA-C03

  1. EC2 Instance Types

    • Naming convention (m5.2xlarge)
    • General Purpose vs Compute vs Memory vs Storage Optimized
    • t2.micro free tier

  2. Security Groups

    • Virtual firewall (allow rules only)
    • Inbound/Outbound rules
    • Timeout = Security Group issue
    • Classic ports: 22 (SSH), 80 (HTTP), 443 (HTTPS), 3389 (RDP)

  3. IAM Roles for EC2

    • Never use aws configure on EC2
    • Attach IAM Roles instead
    • Temporary credentials via Instance Metadata

  4. Purchasing Options

    • On-Demand: No commitment, highest cost
    • Reserved: 1-3 years, up to 72% off
    • Savings Plans: Commit $/hour, flexible
    • Spot: Up to 90% off, can be interrupted
    • Dedicated Hosts: BYOL, compliance

  5. Spot Instances

    • 2-minute interruption warning
    • One-time vs Persistent requests
    • Cancel request BEFORE terminating instances
    • Spot Fleets and allocation strategies

Quick Reference

Instance Type Prefixes

Prefix Type Use Case
t, m General Purpose Web servers, dev
c Compute Optimized Batch, ML, gaming
r, x, z Memory Optimized Databases, caching
i, d, h Storage Optimized OLTP, warehousing

Purchasing Options Comparison

Option Discount Commitment Interruption
On-Demand 0% None No
Reserved 72% 1-3 years No
Savings Plans 72% 1-3 years No
Spot 90% None Yes

Classic Ports

SSH (Linux):    22
RDP (Windows):  3389
HTTP:           80
HTTPS:          443

Hands-On Checklist

  • Set up AWS Budget (zero-spend + monthly)
  • Launch EC2 instance with User Data
  • Configure Security Group rules
  • SSH into instance (any method)
  • Attach IAM Role to EC2
  • View Spot pricing history
  • Understand instance lifecycle (stop/start/terminate)
  • IAM Fundamentals - IAM basics before EC2
  • EBS & EFS (next section) - Storage for EC2
  • ELB & ASG (upcoming) - Load balancing and scaling

Check yourself

Quiz