Linux and DevOps Cheat Sheets (Free PDF Pack)

The Linux cheat sheets and DevOps cheat sheets on ComputingForGeeks are gathered on this page, and one email gets you 23 of them as a single printable PDF. The sheets are grouped by what you run every day: Linux servers, networking and CCNA, containers and Kubernetes, AI coding tools, and databases.

Each group names the sheets we would open first and why. The full library sits at the bottom, newest first, and fills itself in as each new sheet is filed under Cheat Sheets. We checked every link and built the cheat sheets PDF pack in October 2026, and many of the sheets were tested on both Ubuntu 26.04 and Rocky Linux 10.

Which Linux cheat sheets should you start with?

Open the Linux commands cheat sheet, because it is the one that shows where Ubuntu and Rocky Linux now disagree. Ubuntu 26.04 runs Rust rewrites of ls, cat and date while Rocky Linux 10 keeps an older GNU coreutils, so a flag that works on one box can fail on the other. Once that is on your wall, add the sheet for the tool you touch most:

• The systemctl cheat sheet explains why a root systemctl reboot can refuse to run while a backup holds an inhibitor lock.
• The SSH commands sheet covers keys, tunnels, jump hosts and hardening, run on Rocky Linux 10 and Ubuntu 24.04.
• The tmux cheat sheet shows the Ubuntu 26.04 attach error and the Rocky Linux 10 capture-pane crash.
• The OpenSSL cheat sheet generates a post-quantum ML-DSA key with the same genpkey command you use for RSA.
• The UFW commands sheet shows a published Docker port answering on a port UFW never allowed.

Package managers get their own sheets, one per distro family. Arch users want the pacman and yay cheat sheet. openSUSE admins get the zypper sheet, which leads with why zypper dup is the wrong habit on Leap. Fedora users want the dnf5 cheatsheet, which tracks the repo files Fedora 45 moved out of /etc/yum.repos.d. Smaller references round out the shelf: the AppArmor sheet, the terminal shortcuts, Stratis storage and Postfix administration.

Which networking and CCNA cheat sheets are there?

There are three, and they split cleanly between Linux hosts and Cisco gear. If you manage servers, the nmcli sheet is the one to keep open, because changing an IP over SSH is the classic way to lock yourself out and the sheet shows the built-in rollback that prevents it. If you are studying for the CCNA, print the other two and keep them next to your lab:

• The nmcli cheat sheet covers static and DHCP addresses, bonds, bridges, VLANs and safe remote changes.
• The subnetting cheat sheet puts the common IPv4 masks, host counts and wildcard masks on one page.
• The CCNA command cheat sheet groups the IOS commands for device setup, VLANs, OSPF and verification.

Two older comparison sheets, netstat vs ss and ifconfig vs ip, are still in the library below for anyone moving off the net-tools commands.

Which DevOps cheat sheets cover containers and Kubernetes?

The Docker and Podman sheets are the strongest in this group, because both were written in October 2026 around changes that break older notes. On a fresh Docker Engine install, images live in the containerd store and Compose jumped from v2 to v5, while podman pull nginx works on Rocky Linux 10 and fails on Ubuntu 26.04 with a short-name error. Pick the sheets that match your stack:

• The Docker cheat sheet covers the CLI, Compose, cleanup and the firewall and SELinux traps on servers.
• The Podman cheat sheet covers rootless containers, pods, Quadlet services and the Docker compatibility layer.
• The kubectl cheat sheet keeps only the commands that still work on a current cluster, with the output they printed.
• The virsh commands sheet flags the three KVM commands that can cost you data without a warning.
• The Ansible cheat sheet was run against an Ubuntu 26.04 node and a Rocky Linux 10 node with SELinux enforcing.
• The GitHub CLI cheat sheet drives pull requests, Actions runs and the gh api layer from the terminal.

The kubectl sheet is the only one in that list without a PDF yet, so it is not in the pack. Everything else in the list is. Self-hosters and automation users also have smaller-scope sheets for Ansible Vault, the CasaOS and ZimaOS CLI, the FileBrowser CLI and Filestash, none of which has a PDF yet.

Which AI coding tool cheat sheets are there?

AI coding tools are the busiest shelf and the one that goes stale fastest, because these CLIs rename flags and change defaults between releases. The Claude Code cheat sheet was the most-read page on the whole site within days of launch, and the Codex CLI sheet puts every removed flag next to the exact error it now prints. That lets you fix an old script in one pass. For the rest, match the sheet to the tool you have installed:

• The Gemini CLI cheat sheet lists the exit codes, policy files and settings schema a headless run depends on.
• The OpenCode CLI cheat sheet covers OpenCode 2 first and marks what changed from the 1.x line.
• The Antigravity CLI cheat sheet covers every agy flag, slash command and MCP setting.
• The Ollama commands cheat sheet covers the CLI, the REST and OpenAI-compatible APIs, and the Modelfile.
• The Ollama models cheat sheet picks a model for each VRAM tier, with measured tokens per second.

All seven are in the PDF pack. The Aider cheat sheet is on the site too, but it has no PDF yet.

Are there database cheat sheets?

Only two so far, and neither is in the PDF pack. The Qdrant cheat sheet covers the vector database’s REST and gRPC calls, filters, snapshots and cluster operations, and pairs well with the Ollama sheets if you are building a RAG stack. For MySQL and MariaDB, the database size query is a single reference query rather than a full sheet. PostgreSQL has no cheat sheet here yet, so if that is what you run, check the library below for new arrivals.

How do you get the cheat sheets as PDFs?

Enter your email in the form near the top of this page and a download button for the full pack appears as soon as you subscribe. The pack is one 2 MB file with 23 sheets on 24 pages, one landscape page per sheet except one that runs to two, and the PDF bookmarks jump straight to each tool. If you only want one sheet, its own page has a form for that single PDF. The table shows what the pack holds today, by group:

The pack is a snapshot of the PDFs that existed when we built it, so a sheet published later will not be inside it. That sheet’s own page carries its download form from day one, which means the per-sheet forms are always the current source and the pack is the convenient bundle.

Every post in the Cheat Sheets category

Below is every post in the Cheat Sheets category, newest first, so a new sheet filed there shows up the moment it is published. Some older entries are command guides rather than one-page sheets, and most of the sheets linked in the groups above are not filed in this category yet. Use the group links as the curated starting point and this list for the rest.

If a sheet you rely on isn’t here, the groups above link the rest of the library, and the PDF pack covers the 23 sheets that already have a printable version.