ufwBasicOperations.sh

#
# UFW, or Uncomplicated Firewall, is an interface to iptables that is geared towards simplifying 
# the process of configuring a firewall. While iptables is a solid and flexible tool, it can be difficult for beginners 
# to learn how to use it to properly configure a firewall. If you’re looking to get started securing your network, 
# and you’re not sure which tool to use, UFW may be the right choice for you.
#
#This tutorial will show you how to set up a firewall with UFW on Ubuntu 18.04.
#

# Installation
# UFW is installed by default on Ubuntu. If it has been uninstalled for some reason, you can install it with 
sudo apt install ufw

# Enabling ufw
sudo ufw enable

# Setup default policy
sudo ufw default deny incoming
sudo ufw default allow outgoing

# Allowing SSH Connections
sudo ufw allow ssh
# or
sudo ufw allow 22

# Allowing Other Connections 
sudo ufw allow http 
#or 
sudo ufw allow 80

# NOTE: if you dont specify tcp/udp, then it will apply on both, but you can setup for tcp/udp only, like this:
sudo ufw allow 80/tcp

sudo ufw allow https 
#or 
sudo ufw allow 443

# Allow Specific Port Ranges for example
sudo ufw allow 6000:6007/tcp
sudo ufw allow 6000:6007/udp

#Advanced Rules
#To allow connections from an IP address:
sudo ufw allow from 204.61.105.10

#To allow connections from a specific subnet:
sudo ufw allow from 204.61.105.10/24

#To allow a specific IP address/port combination:
sudo ufw allow from 204.61.105.10 to any port 22 proto tcp

# Remove a rule
sudo ufw delete allow 80

# See the rules that are currently set
sudo ufw status verbose

# disable ufw
sudo ufw disable