Firewall (UFW)¶

All servers run UFW with default deny incoming.

Common Open Ports¶

Port	Purpose	Servers
22	SSH	All
80	HTTP	All
443	HTTPS	All
25	SMTP	VPS1, VPS2
465	SMTPS	VPS2
587	SMTP Submission	VPS2
993	IMAPS	VPS2
3306	MariaDB	VPS2 (remote)
51820/UDP	WireGuard	VPS3

Management¶

# Check status
sudo ufw status verbose

# Allow port
sudo ufw allow 80/tcp

# Deny IP
sudo ufw deny from {ip}

# Delete rule
sudo ufw delete allow 80/tcp