This script allows you to quickly block source IP addresses, say during an attempted attack with Ubuntu's UFW

Block Source IP Addresses (UFW)

#!/bin/bash
# Check if root
if [ "$(whoami)" != "root" ]; then
echo "Not running as root. Exiting..."
exit 0
else
echo "Editing and Reviewing UFW Firewall Entries"
fi

sudo ufw status numbered

read -p 'Please review the above rules-The IP entry you add in the next step will add it to the top of the hierarchy....'

read -p "IP Address to Block/CIDR: " IP_ADDRESS

echo "*****************************"
echo "Source IP Address to Block:" $IP_ADDRESS
echo "*****************************"

echo "Is the information listed above correct? [Y,n]"
read input
if [[ $input == "Y" || $input == "y" ]]; then
sudo ufw insert 1 deny from $IP_ADDRESS to any
else
sudo ufw status numbered
echo "No Changes Made"
exit 0
fi