Devops Guide

DevOps & Infrastructure Guide

Master modern DevOps practices, containerization, orchestration, and cloud platforms.

Quick Start

Docker Basics

# Dockerfile example
FROM node:18-alpine
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
EXPOSE 3000
CMD ["node", "index.js"]

Kubernetes Deployment

# Simple K8s deployment
apiVersion: apps/v1
kind: Deployment
metadata:
  name: app-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: myapp:1.0
        ports:
        - containerPort: 3000

Terraform Infrastructure

# AWS EC2 with Terraform
resource "aws_instance" "web" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"

  tags = {
    Name = "web-server"
  }
}

DevOps Technology Stack

Containerization

• Docker: Images, containers, registry
• Docker Compose: Multi-container orchestration
• Image Security: Scanning, signing, base image selection
• Best Practices: Minimal images, layer caching, security

Container Orchestration

• Kubernetes: Pods, Services, Deployments, StatefulSets
• Helm: Package management for Kubernetes
• Service Mesh: Istio, Linkerd for networking
• Container Security: RBAC, NetworkPolicies, Pod Security

Infrastructure as Code

# Terraform modules
module "network" {
  source = "./modules/network"
  vpc_cidr = "10.0.0.0/16"

  public_subnets = [
    "10.0.1.0/24",
    "10.0.2.0/24"
  ]
}

• Terraform: HCL, state management, modules
• Ansible: Agentless configuration management
• CloudFormation: AWS native IaC
• Pulumi: Infrastructure as code with programming languages

Cloud Platforms

AWS

• Compute: EC2, ECS, EKS, Lambda
• Storage: S3, EBS, EFS
• Database: RDS, DynamoDB, ElastiCache
• Networking: VPC, ALB, CloudFront
• Security: IAM, KMS, Secrets Manager

Other Platforms

• Google Cloud Platform: Compute Engine, Cloud Run, GKE
• Azure: VMs, App Service, AKS
• DigitalOcean: Simpler alternative, good for learning

CI/CD Pipelines

Popular Platforms

• GitHub Actions: Integrated with GitHub
• GitLab CI: GitLab native CI/CD
• Jenkins: Self-hosted, highly customizable
• CircleCI: Cloud-based, easy setup

# GitHub Actions example
name: Deploy
on:
  push:
    branches: [main]

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Run tests
        run: npm test
      - name: Build
        run: npm run build
      - name: Deploy
        run: ./deploy.sh

Monitoring & Logging

Monitoring

• Prometheus: Metrics collection
• Grafana: Visualization and dashboards
• Datadog: Cloud monitoring service
• New Relic: Application performance monitoring

Logging

• ELK Stack: Elasticsearch, Logstash, Kibana
• Splunk: Log aggregation and analysis
• Cloudwatch: AWS native logging

Alerting

• PagerDuty: On-call management
• Alertmanager: Prometheus alerting
• Opsgenie: Alert and incident response

Linux Administration

System Management

# Common commands
systemctl start/stop/restart service-name
journalctl -u service-name                  # View logs
ps aux | grep process-name                  # Process info
top/htop                                    # System monitoring

• User and permission management
• Package managers (apt, yum, pacman)
• Systemd services
• Shell scripting and automation
• Network configuration

DevOps Workflow

Development → Production

1. Plan: Design infrastructure
2. Code: Write application and IaC
3. Build: Containerize, create artifacts
4. Test: Unit, integration, security tests
5. Deploy: Stage and production deployment
6. Monitor: Metrics, logs, alerts
7. Optimize: Performance tuning

Deployment Strategies

• Blue-Green: Two identical environments
• Canary: Gradual rollout to subset
• Rolling: Gradually replace old version
• Feature Flags: Toggle features safely

Security Best Practices

Container Security

• Scan images for vulnerabilities
• Run as non-root user
• Use minimal base images
• Sign images

Infrastructure Security

• Network policies and firewalls
• Encryption in transit and at rest
• Secrets management
• IAM principle of least privilege

Learning Resources

Hands-On Platforms

• Katakoda: Interactive learning environments (archived)
• Play with Docker: Browser-based Docker practice
• Linux Academy: DevOps courses
• A Cloud Guru: AWS and cloud courses

Official Documentation

• Kubernetes Docs
• Docker Docs
• Terraform Docs
• AWS Documentation

Practice Projects

1. Docker Multi-container App - Docker Compose setup
2. Kubernetes Deployment - Deploy app with services
3. Terraform Infrastructure - Complete AWS setup
4. CI/CD Pipeline - Build and deploy workflow
5. Monitoring Stack - Prometheus + Grafana

Next Steps

1. Learn Docker fundamentals
2. Practice Kubernetes basics
3. Choose cloud platform (AWS recommended)
4. Learn Infrastructure as Code (Terraform)
5. Set up CI/CD pipeline
6. Implement monitoring and logging
7. Master Linux administration

Roadmap.sh Reference: https://roadmap.sh/devops

Status: ✅ Production Ready | SASMP: v1.3.0 | Bonded Agent: 03-devops-cloud-specialist