AWS: EC2

EC2: Elastic Compute Cloud

AWS Budget Setup
- Root User: Billing and Cost Management > Account > Billing and Payments > IAM user and role access to Billing information: ✅ Activate IAM Access > Update
- IAM User:
  - Billing and Cost Management > Bills > Charges by service
  - Billing and Cost Management > Free Tier
  - Billing and Cost Management > Budgets > Create Budget
  - Choose budget type: Use a template (Simplified)
  - Template: Zero Spend Budget
  - Budget Name: My zero-spend budget
  - Email Recipients: mohammedimransharif@proton.me
  - Create Budget

EC2 Basics
- Amazon EC2:
- EC2 Sizing & Configuration Options:
  - Operating System (OS): Linux, Windows, or macOS
  - CPU: Compute power and number of cores
  - RAM: Memory allocation
  - Storage Options:
    - Network-attached: EBS and EFS
    - Local hardware: EC2 Instance Store
  - Network: Speed, public IP address
  - Security: Firewall rules via security groups
  - Bootstrap script: EC2 User Data
- EC2 User Data:
  - You can bootstrap instances using EC2 User Data scripts.
  - Bootstrapping: Running commands at first launch
  - Runs only once on initial startup
  - Automates boot-time tasks like:
    - Installing updates
    - Installing software
    - Downloading files
    - Custom initialization
  - Runs as the root user
- EC2 Instance Types:

Instance	vCPU	Mem (GiB)	Storage	Network Performance	EBS Bandwidth
t2.micro	1	1	EBS-Only	Low to Moderate	—
t2.xlarge	4	16	EBS-Only	Moderate	—
c5d.4xlarge	16	32	1 × 400 NVMe SSD	Up to 10 Gbps	4750
r5.16xlarge	64	512	EBS-Only	20 Gbps	13600
m5.8xlarge	32	128	EBS-Only	10 Gbps	6800

Launch an EC2 Instance running Linux
- We'll create our first virtual server using the AWS Console.
- This helps us understand the parameters involved in launching an instance.
- We'll automate setup using EC2 User Data for web server configuration.
- We'll also learn how to start, stop, and terminate the instance.
Steps:
- EC2 > Instances > Launch an instance
- Name: My First Instance
- Key Pair: Create New > Name: EC2 tutorial > Download
- Network Settings: ✅ Allow HTTP traffic from the internet
- User Data (bootstrap script):
```
#!/bin/bash
# use this for your user data (script from top to bottom)
# install httpd (Linux 2 version)
yum update -y
yum install -y httpd
systemctl start httpd
systemctl enable httpd
echo "<h1>Hello World from $(hostname -f)</h1>" > /var/www/html/index.html
      
```
- Click Launch Instance
- Go to: EC2 > Instances > ✅ Select your instance
- View Public IPv4 address > Open in browser using http://
- Note: Public IP changes on reboot; Private IP remains constant.

Overview: Choose EC2 instances optimized for different use cases.
Ref: aws.amazon.com/ec2/instance-types
General Purpose
- Great for diverse workloads such as web servers or code repositories.
- Balanced compute, memory, and networking resources.
- t2.micro is commonly used in tutorials and free-tier setups.
Compute Optimized
- Ideal for compute-intensive tasks that require high-performance processors:
- Example: C8g
Memory Optimized
- Best for workloads that process large datasets in memory.
- Use cases:
  - Relational/non-relational databases
  - Distributed cache stores
  - In-memory BI databases
  - Real-time big data processing
- Examples: R7g, R7i, R7iz
Accelerated Computing – Uses hardware accelerators like GPUs for ML, AI, and graphics workloads.
Storage Optimized
- Optimized for high, sequential read/write access to local storage.
- Use cases:
  - OLTP systems
  - Relational & NoSQL databases
  - In-memory cache (e.g., Redis)
  - Data warehousing applications
  - Distributed file systems
- Example: i8g
Instance Features – Naming convention:
- m: instance class
- 5: generation
- 2xlarge: size within the class
To compare instances across families and specs, visit ec2instances.info

Introduction to Security Groups
- Fundamental component of AWS network security
- Control how traffic is allowed into/out of EC2 instances
- Contain only allow rules
- Rules can reference IP addresses or other security groups
Security Groups – Deeper Dive
- Act as a virtual firewall at the EC2 level
- Regulate:
  - Port access
  - IP ranges (IPv4 and IPv6)
  - Inbound traffic (external → instance)
  - Outbound traffic (instance → external)
Security Groups – Good to Know
- Can be attached to multiple instances
- Scoped to a region/VPC pair
- If traffic is blocked, the EC2 instance won't detect it
- Best practice: Use a separate security group for SSH
- If the app times out → likely security group issue
- If the app gives “connection refused” → app issue or not running
- All inbound traffic is blocked by default
- All outbound traffic is allowed by default
Common Ports
- 22 – SSH (Linux login)
- 21 – FTP (upload files)
- 22 – SFTP (secure file upload)
- 80 – HTTP (unsecured websites)
- 443 – HTTPS (secured websites)
- 3389 – RDP (Windows login)
Security Groups – Hands-On
- Go to: EC2 > Network & Security > Security Groups
- Select security group > Configure Inbound/Outbound rules
- Add, remove, or modify rules as needed
SSH Overview