Phase Verbs / Action Phrases
| Phrase | Meaning |
|---|---|
| rent (virtual machines) | pay to use compute resources without owning hardware |
| configure (an instance) | choose OS, CPU, RAM, storage, network settings |
| bootstrap (an instance) | run startup commands automatically on first launch |
| distribute (load) | spread traffic across multiple instances |
| scale (services) | increase or decrease compute capacity automatically |
Technical Vocabulary
| Term | Definition |
|---|---|
| EC2 (Elastic Compute Cloud) | AWS’s most popular IaaS service — rent virtual servers on demand |
| EC2 Instance | A single virtual server rented from AWS |
| IaaS (Infrastructure as a Service) | Cloud model where you rent the infrastructure (servers, networking) |
| EBS (Elastic Block Store) | Network-attached persistent storage for EC2 |
| EFS (Elastic File System) | Managed file system for EC2 (shared across instances) |
| EC2 Instance Store | Hardware-attached storage (ephemeral, but very fast) |
| Elastic Load Balancer (ELB) | Distributes incoming traffic across multiple EC2 instances |
| Auto Scaling Group (ASG) | Automatically adds/removes EC2 instances based on demand |
| Security Group | Virtual firewall controlling inbound/outbound traffic to an EC2 instance |
| EC2 User Data | A bootstrap script that runs once when an instance first starts |
| Bootstrapping | Automating setup tasks (install software, download files) at first boot |
| AMI | Amazon Machine Image — a template for launching EC2 instances (includes OS + config) |
Key Concepts
What is EC2?
- Stands for Elastic Compute Cloud
- Lets you rent virtual machines called EC2 instances
- Covers more than just VMs — it is the full compute stack:
- Virtual machines → EC2 instances
- Storage → EBS volumes (network-attached)
- Load balancing → ELB
- Auto-scaling → ASG
What You Configure Per Instance
| Dimension | Choices |
|---|---|
| Operating System | Linux (most common), Windows, macOS |
| CPU | Number of cores |
| RAM | Amount of memory |
| Storage | Network-attached (EBS/EFS) or hardware-attached (Instance Store) |
| Network | Speed, public IP assignment |
| Firewall | Security Group rules |
| Startup Script | EC2 User Data |
EC2 User Data
- A bash/shell script you provide at launch
- Runs once only — on first start
- Purpose: automate boot tasks (install updates, install software, download files)
- Runs as the root user (has sudo rights)
Exam Tips
- EC2 = “Infrastructure as a Service” — renting compute on demand
- Know the 6 dimensions you configure: OS, CPU, RAM, storage, network, firewall
- User Data script: runs once, at first launch, as root
- EBS = network-attached (persistent); Instance Store = hardware-attached (ephemeral)