Discussing when a firewall is needed in Linux and I show how to check what services you have open on your system. I also give a quick explanation about computer networking protocols ICMP, TCP, and UDP. Checking services: $ ss -nltup Scanning System: $ sudo nmap -sS ip $ sudo nmap -sU -p “udp ports” ip Tutorial Videos: Debian nftables: https://www.youtube.com/watch?v=_A-Q6yTMX0g Ubuntu UFW: https://www.youtube.com/watch?v=BJNXrV9G3QE Like my channel? Please help support it: Patreon: https://www.patreon.com/quidsup Paypal: https://www.paypal.me/quidsup Follow me on Social Media Twitter: https://twitter.com/quidsup MeWe: https://mewe.com/i/quidsup Minds: https://minds.com/quidsup #Firewall #Linux #Cybersecurity