ck’s notes

Linux machine checklist

Quick sanity checks after setting up a new machine:

sudo apt update && sudo apt upgrade -y
timedatectl set-timezone UTC
hostnamectl set-hostname mybox
systemctl --failed

Also worth doing: set up automatic updates, check disk space, and make sure time sync is working.

Useful shell snippets

Commands I reach for often enough to write down:

# disk usage, sorted
du -sh /* 2>/dev/null | sort -hr | head -10

# find large files under current directory
find . -type f -size +50M -exec ls -lh {} \;

# archive a folder with tar
tar -czf archive.tar.gz /path/to/folder

# check last reboot time
who -b

Static website setup

Setting up a lightweight static site with Caddy:

# Install Caddy on Ubuntu
sudo apt install -y debian-keyring debian-archive-keyring
curl -1sLf https://dl.cloudsmith.io/public/caddy/stable/gpg.key \
  | sudo gpg --dearmor -o /usr/share/keyrings/caddy-stable.gpg

# Minimal Caddyfile
example.com {
    root * /var/www/site
    file_server
}

TLS is automatic. No certbot, no cron, no extra config — Caddy handles Let’s Encrypt renewal in the background.

Backup reminders

Minimal backup habits for small setups:

• Copy /etc to a tarball before any config change.
• Keep at least three dated snapshots of critical files.
• Test restore on a spare machine at least once — a backup you haven’t tested isn’t a backup.
• If you generate data, push it somewhere else (external drive, cloud storage, or even a local rsync).