$ curl cheat.sh/
# ufw
# Uncomplicated Firewall.
# Frontend for iptables aiming to make configuration of a firewall easier.
# More information: <https://wiki.ubuntu.com/UncomplicatedFirewall>.

# Enable ufw:
ufw enable

# Disable ufw:
ufw disable

# Show ufw rules, along with their numbers:
ufw status numbered

# Allow incoming traffic on port 5432 on this host with a comment identifying the service:
ufw allow 5432 comment "Service"

# Allow only TCP traffic from 192.168.0.4 to any address on this host, on port 22:
ufw allow proto tcp from 192.168.0.4 to any port 22

# Deny traffic on port 80 on this host:
ufw deny 80

# Deny all UDP traffic to ports in range 8412:8500:
ufw deny proto udp from any to any port 8412:8500

# Delete a particular rule. The rule number can be retrieved from the `ufw status numbered` command:
ufw delete rule_number

$
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