Linux
SSH Hardening Checklist for Ubuntu Servers
Lock down SSH on Ubuntu 24.04 without locking yourself out: keys only, no root, the cloud-init drop-in trap, socket activation, verification.
Linux
Linux server guides from real setups: Ubuntu and Debian, systemd, firewalls, backups, mail and the gotchas that bite in production.
Linux
Palworld Dedicated Server on Linux with SteamCMD
Palworld dedicated server on Ubuntu via SteamCMD: native Linux build, systemd unit, the empty PalWorldSettings.ini trap, steamclient.so fix, backups.
Linux
rsync Backups That Actually Work — No Excuses
rsync backups that hold up: trailing-slash rules, dry runs, hard-link snapshots with --link-dest, rotation, pull over SSH with rrsync, a timer.
Linux
Installing Docker on Ubuntu the Right Way (Not the Snap Version)
Install Docker Engine + the compose plugin from Docker's official apt repo on Ubuntu/Debian, ditch the snap, and fix log growth and the UFW bypass.
Linux
Linux Disk Full: Finding What's Eating Your Space
Disk full on Linux: df, du, ncdu, deleted-but-open files, inodes, journald, Docker and snap leftovers, and how to free space safely.
Linux
Run Your Own Daemon with systemd — Writing Service Unit Files
Write a systemd service unit that survives reboots and crashes: anatomy, restart policy, env files, sandboxing, drop-in overrides, gotchas.
Linux
Nginx Reverse Proxy: The Config I Actually Use
A working nginx reverse proxy on Ubuntu: proxy headers, WebSockets, Let's Encrypt via certbot, a catch-all server, and the 502/413 gotchas.
Linux
UFW Firewall Rules That Don't Lock You Out
UFW on Ubuntu and Debian without the lockout: SSH first, a dead-man switch, rule order, subnet and game ports, and the Docker bypass.
Linux
fail2ban: Stop Getting Hammered on SSH and Nginx
fail2ban for SSH and nginx on Ubuntu 24.04 / Debian 12-13: jail.local, systemd backend, a custom scanner filter, testing with fail2ban-regex, and gotchas.
Linux
The Sysadmin Prompt Cheat Sheet — AI Commands That Actually Work
Copy-paste prompts for sysadmin work with Claude or any LLM: explain commands, write scripts, triage logs, review configs, convert Bash to PowerShell.
Linux
Linux Log Rotation with logrotate — Before Your Disk Fills Up
logrotate for your own apps on Ubuntu/Debian: a working config, create vs copytruncate, postrotate reloads, maxsize, testing with -d, common traps.
Linux
Linux User Management — adduser, Groups, sudo and SSH Keys
Admin and service users on Ubuntu/Debian: adduser vs useradd, groups, sudoers drop-ins, SSH keys with correct permissions, and locking users properly.