DevOps Engineer Roadmap

What Linux is, why backend engineers rely on it, and the major distribution families.

The Linux filesystem hierarchy, reading and changing permissions, and symbolic vs hard links.

Writing a real Bash script with variables, conditionals, loops, and command substitution.

Writing a unit file, controlling it with systemctl, and reading logs with journalctl.

How DNS resolution works step by step, record types, caching and TTLs, and the full journey from URL to rendered page.

Creating branches, fast-forward vs merge commits, and resolving a merge conflict.

A complete GitHub Actions workflow that checks out code, installs dependencies, and runs tests on every push and PR.

Extending a workflow into build, test and deploy stages with secrets and branch-based deployment.

Rolling, blue-green, and canary deployments explained with their trade-offs.

Dependency vulnerability scanning and secret scanning, with real GitHub Actions workflow steps.

What containers are, how they differ from VMs, installing Docker, and your first container.

A complete multi-stage Dockerfile, layer caching, and building images with docker build.

Defining a multi-container app in docker-compose.yml, environment variables, and .env files.

Running as a non-root user, choosing minimal/distroless base images, and scanning images for known vulnerabilities.

What Kubernetes is, its core architecture, and getting started with kubectl.

Pods, a complete Deployment example with rolling updates, and the three Service types.

Externalizing configuration with ConfigMaps and Secrets, and autoscaling with the HPA.

What Helm solves, a real Chart structure, and deploying with helm install and helm upgrade.

The core AWS mental model: pay-for-what-you-use, managed services, regions, and Availability Zones.

Users, groups, roles and policies, the principle of least privilege, and a real IAM policy JSON example.

VPC subnets, why databases live in private subnets, and the value of a managed database with RDS.

The problem Infrastructure as Code solves, installing Terraform, and terraform init.

Parameterizing configuration with variables and outputs, building a reusable module, and managing environments with workspaces.

Configuring proxy_pass with forwarded headers, and load balancing across an upstream pool of servers.

A complete HTTPS server block, redirecting HTTP to HTTPS, and certificate basics with Let's Encrypt/Certbot.

Centralized logging with a DaemonSet-based collector, liveness vs readiness probes, and debugging with kubectl logs/describe.

SSH key authentication, disabling root login and passwords, and basic brute-force protection with fail2ban.

Right-sizing, Reserved vs On-Demand vs Spot instances, and common AWS cost pitfalls.

Common Kubernetes interview questions covering Pods, Deployments, Services, Helm, Ingress, and production readiness.