Can you explain what the Fail2ban tool is and what it is used for?

Fail2ban is a security tool for Linux servers that automatically blocks IP addresses from which suspicious access attempts occur, such as multiple failed SSH login attempts.

It works by analyzing system service logs, identifying repeated errors or suspicious activity, and adding rules to the firewall (usually iptables) to temporarily block these IPs. This helps protect the server from brute-force attacks and other unauthorized access.

Example of use: if the same IP repeatedly enters an incorrect password via SSH, Fail2ban will automatically block that IP for a specified period.