ConfigServer Security & Firewall (CSF)

ConfigServer Security & Firewall (CSF) is a security application for Linux that provides a stateful packet inspection (SPI) firewall, intrusion detection, and other protective features. It is used to control access and protect the server from common attacks.

CSF works by examining the state of network connections to filter traffic. It includes the Login Failure Daemon (LFD) process, which automatically blocks IP addresses that show signs of brute-force login attempts against server services. The firewall allows for granular control, such as blocking traffic from entire countries and limiting connection rates. CSF also integrates directly with control panels like cPanel and InterWorx.

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