UFW Ubuntu Firewall
From Free Knowledge Base- The DUCK Project: information for everyone
To block a port in UFW we use ufw deny command
ufw deny port/protocol
Examples
ufw deny 53
block specific IP address
The syntax is:
sudo ufw deny from {ip-address-here} to any
To block or deny all packets from 192.168.1.5, enter:
sudo ufw deny from 192.168.1.5 to any