DevOps & Linux Engineering

DevOps is the practice of building, shipping, and running software quickly and reliably by bringing development and operations together. In practice that means you don’t just write code — you also know how to set up a Linux server, install a web server like Nginx, point a domain at it, run a database, automate deployments, and keep the whole thing healthy. This documentation teaches DevOps the way you’d actually learn it on the job: one focused topic per page, in simple friendly language, with the when and why — not just the how — that most tutorials skip.

How these docs are organized

Every page covers a single concept and answers three questions other sites leave out: what it is, when you should (and shouldn’t) use it, and exactly how to do it — with real, copy-pasteable commands you can run on an Ubuntu server. We start from the ground (the Linux command line) and build all the way up to automated pipelines and production reliability. Work top to bottom, or jump straight to what you need.

What you’ll learn

• Getting Started — what DevOps is, the DevOps lifecycle and culture, the roles and tools, and how everything in these docs fits together.
• Linux & Ubuntu Basics — installing Ubuntu, the command line, the filesystem, files and permissions, and the everyday commands you’ll use constantly.
• Linux System Administration — users and groups, sudo, processes, systemd services, cron jobs, packages with apt, disks, and logs.
• Shell Scripting — automating tasks with Bash: variables, conditionals, loops, functions, and writing reusable scripts.
• Networking & SSH — IP addresses, ports, DNS, firewalls (ufw), and securely connecting to servers with SSH and key pairs.
• Git & Version Control — the version-control workflow every DevOps pipeline is built on.
• Web Servers (Nginx & Apache) — installing and configuring Nginx and Apache, virtual hosts, serving static sites, and setting up a reverse proxy in front of your app.
• Domains, DNS & SSL — buying and pointing a domain, configuring DNS records, and getting free HTTPS certificates with Let’s Encrypt and Certbot.
• Databases & Data Stores — installing, securing, and backing up PostgreSQL, MySQL/MariaDB, MongoDB, and Redis on your own servers.
• Application Deployment — deploying Node.js, Java, Python, and static apps with systemd, PM2, and Gunicorn behind a reverse proxy.
• Containers & Docker — packaging apps into images and running them as containers (with deep dives in the Docker docs).
• Kubernetes & Orchestration — what container orchestration is and when you actually need it.
• CI/CD Pipelines — automating build, test, and deploy with GitHub Actions, GitLab CI, and Jenkins.
• IaC & Configuration Management — provisioning and configuring servers repeatably with Ansible and Terraform.
• Cloud & Virtualization — virtual machines, cloud providers, and renting a server to put all of this into practice.
• Monitoring & Observability — metrics, dashboards, and alerts with Prometheus and Grafana.
• Logging — collecting, centralizing, and searching logs.
• Security & DevSecOps — hardening servers, managing secrets, and baking security into the pipeline.
• SRE & Reliability — SLAs/SLOs, incident response, backups, and keeping systems up.

The mindset to keep

Before the first command, hold onto two ideas. First, automate the second time you do anything — if you’ve typed a sequence of commands twice, it belongs in a script or a pipeline. Manual steps are where outages come from. Second, everything is reproducible or it’s a liability — a server you configured by hand and can’t rebuild is a single point of failure, so prefer scripts, Dockerfiles, and infrastructure-as-code over one-off clicks.

New to all of this? Start with What is DevOps?, then go straight into the Linux & Ubuntu Basics section. Almost everything in DevOps runs on Linux, so the command line is the single highest-leverage skill you can build first.