What is the difference between fail2ban and FIREWALL?

Question

linux

Tell knowledgeable people what is the difference between fail2ban and firewall? Should they be used together?
Maybe one firewall will be enough?

Answer 1

fail2ban is up to date . Its direct purpose is to block hosts that pick up your passwords. Usually not the entire Internet is attacked. And if you are attacked from all over the Internet at the same time, this is already ddos ​​and you just lie until it ends, regardless of whether you have fail2ban or not.

Answer 2

fail2ban is a daemon that analyzes logs and uses a packet filter (what you called a firewall) to automatically block addresses from which attacks and / or suspicious activity are coming.

Answer 3

fail2ban uses a firewall. I think lately fail2ban is not relevant, since the attack can be distributed, and you cannot block the entire Internet.