Cloud Computing Course Modules Explained Week by Week

#!/usr/bin/env bash
# Create a role EC2 can assume, with read-only S3 access
set -euo pipefail
cat > trust.json <<'JSON'
{"Version": "2012-10-17",
 "Statement": [{"Effect": "Allow",
   "Principal": {"Service": "ec2.amazonaws.com"},
   "Action": "sts:AssumeRole"}]}
JSON
aws iam create-role --role-name course-ec2-s3-read \
  --assume-role-policy-document file://trust.json
aws iam attach-role-policy --role-name course-ec2-s3-read \
  --policy-arn arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess

VPC 10.0.0.0/16 (ap-south-1)
|
|-- Public subnet A  10.0.1.0/24  (AZ a) -> route 0.0.0.0/0 to Internet Gateway
|-- Public subnet B  10.0.2.0/24  (AZ b) -> route 0.0.0.0/0 to Internet Gateway
|-- Private subnet A 10.0.11.0/24 (AZ a) -> route 0.0.0.0/0 to NAT Gateway
`-- Private subnet B 10.0.12.0/24 (AZ b) -> route 0.0.0.0/0 to NAT Gateway

Security groups:
  web-sg: allow 443 from internet
  app-sg: allow app port from web-sg only
  db-sg:  allow database port from app-sg only

#!/bin/bash
# EC2 user data: runs on first boot (Amazon Linux 2023)
dnf install -y nginx
cat > /usr/share/nginx/html/index.html <<'HTML'
<h1>Cloud course web server</h1>
<p>Served from an EC2 instance.</p>
HTML
systemctl enable --now nginx

{
  "Rules": [
    {
      "ID": "archive-old-reports",
      "Status": "Enabled",
      "Filter": { "Prefix": "reports/" },
      "Transitions": [ { "Days": 30, "StorageClass": "STANDARD_IA" } ],
      "Expiration": { "Days": 365 }
    }
  ]
}

# Apply with:
# aws s3api put-bucket-lifecycle-configuration --bucket <name> \
#   --lifecycle-configuration file://lifecycle.json

#!/usr/bin/env bash
# Alarm when average CPU stays above 70% for 10 minutes
set -euo pipefail
INSTANCE_ID=${1:?usage: $0 <instance-id>}
aws cloudwatch put-metric-alarm \
  --alarm-name "course-high-cpu-$INSTANCE_ID" \
  --namespace AWS/EC2 --metric-name CPUUtilization \
  --dimensions Name=InstanceId,Value="$INSTANCE_ID" \
  --statistic Average --period 300 --evaluation-periods 2 \
  --threshold 70 --comparison-operator GreaterThanThreshold

# main.tf (Terraform >= 1.5)
terraform {
  required_providers { aws = { source = "hashicorp/aws", version = "~> 5.0" } }
}
provider "aws" { region = var.region }

variable "region" { default = "ap-south-1" }

module "vpc" {
  source  = "terraform-aws-modules/vpc/aws"
  version = "~> 5.0"
  name    = "course-vpc"
  cidr    = "10.0.0.0/16"
  azs             = ["ap-south-1a", "ap-south-1b"]
  public_subnets  = ["10.0.1.0/24", "10.0.2.0/24"]
  private_subnets = ["10.0.11.0/24", "10.0.12.0/24"]
}

Week  Topic                        Lab done  Notes written  Cleaned up
1     Cloud basics, account safety   [ ]       [ ]            [ ]
2     IAM                            [ ]       [ ]            [ ]
3     Networking                     [ ]       [ ]            [ ]
4     Compute                        [ ]       [ ]            [ ]
5     Load balancing, scaling        [ ]       [ ]            [ ]
6     Storage                        [ ]       [ ]            [ ]
7     Databases                      [ ]       [ ]            [ ]
8     Monitoring                     [ ]       [ ]            [ ]
9     Security and cost              [ ]       [ ]            [ ]
10-11 Terraform                      [ ]       [ ]            [ ]
12    Capstone                       [ ]       [ ]            [ ]

Capstone: highly available web application

- VPC with public and private subnets in two zones (Terraform)
- Load balancer + auto scaling web tier
- Private RDS database with backups
- S3 bucket for static files with lifecycle rules
- CloudWatch alarms and a dashboard
- Encryption, least-privilege IAM, budget alert
- Architecture diagram, README, teardown command

Each week:
  Attend classes and take notes
  Repeat the lab on your own without notes
  Write five interview-style questions for the topic and answer them
  Clean up resources and check the billing page
  Push code and notes to Git