Server & Admin Tools

Practical chmod and chown cheatsheet, most-wanted first: chmod +x to make a script executable, the numeric model (read 4, write 2, execute 1) so 755 is rwx for you and...

Practical systemd cheatsheet, most-wanted first: systemctl status to see if a service runs and why it died, restart, reload, enable --now to start now and on boot, daemon-reload after editing...

Practical Linux rsync cheatsheet, most-wanted first: mirror a folder with rsync -av, copy over ssh with -avz to user@host, mirror exactly with --delete, dry run with -avn or --dry-run, progress...

Build .htpasswd lines in your browser with Apache MD5 (apr1), SHA-512 crypt or SHA1. Multi-user list, copy all, nginx and Apache snippets. Nothing leaves the page.

Searchable Linux errno reference. Look up any errno by number or symbolic name (EPERM, ENOENT, EACCES, ECONNREFUSED and more), with the meaning, real causes and how to diagnose and fix...

Practical decision framework for choosing a Linux distribution in 2026. Four real inputs (team skills, compliance, application stack, support model), decision tree, distro profiles, fleet diversity strategy, hidden costs.

Practical 2026 migration playbook from CentOS 7 or 8 to Rocky Linux 9 (or AlmaLinux 9). ELevate in-place path, fresh install path, pre-flight inventory, post-migration validation, common breaks and fixes.

In-depth comparison of the four Linux firewall tools in 2026: iptables, nftables, firewalld, ufw. Per-distro defaults, same rule in four syntaxes, performance and feature comparison, migration patterns, decision tree.

Deep-dive comparison of Linux network stacks (netplan, ifupdown, NetworkManager, systemd-networkd, wicked) across Ubuntu, Debian, Fedora, Rocky, Arch, openSUSE, Alpine. Static IP recipes, migration patterns, decision tree.

Pick your Linux distro (Ubuntu, Debian, Fedora, Rocky, Arch, openSUSE, Alpine) and a topic (network, firewall, services, logs, packages, users, system, storage), get the quick command, files, workflow, verify and...