Quick references for running Linux servers, SSH, and the tools on my Mac.
Keys and 1Password, the ~/.ssh/config file, adding keys to EC2, copying files, removing access, and troubleshooting.
Step-by-step setup: turn on 1Password's SSH agent, add keys, save their public halves, and point each server's config entry at 1Password.
Installing Homebrew fresh, everyday commands, updates, Mac apps (casks), a Brewfile for a new Mac, and fixes.
Ubuntu virtual machines: setting one up, ssh, moving files, snapshots, the background helper, and the stuck-resume fix.
Getting around, reading files and logs, disk space, permissions, server health, and services. Amazon Linux 1 and Ubuntu 24.04 side by side.
Installing and updating with apt, the safe update routine, automatic security updates, holds, PHP versions for Moodle, and fixes.
What end of life means, checking what's installed, changing things carefully with yum, history, and a yum ↔ apt translation table.
Who's affected, the first five minutes, symptom to cause, then Apache, PHP-FPM, RDS, network and SSL, and Moodle itself.