apt install ufw
ufw default deny incoming
ufw default allow outgoing
ufw default allow routed
ufw allow from 192.168.0.0/16
ufw allow from 172.16.0.0/12
ufw allow from 10.0.0.0/24
ufw allow 8899/tcp
ufw enable
ufw status verbose
systemctl enable ufw
systemctl restart ufw