O PortSentry vem com o cPanel por padrão e, portanto, é instalado em seu sistema quando você instala o cPanel. Se você tem o cPanel instalado, não há nada para se preocupar.
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A port scan is a symptom of a larger problem coming your way. It is often the pre-cursor for an attack and is a critical piece of information for properly defending your information resources. PortSentry is a program designed to detect and respond to port scans against a target host in real-time and has a number of options to detect port scans. When it finds one it can react in the following ways:
A log indicating the incident is made via syslog(). The target host is automatically dropped into /etc/hosts.deny for TCP Wrappers. The local host is automatically re-configured to route all traffic to the target to a dead host to make the target system disappear. The local host is automatically re-configured to drop all packets from the target via a local packet filter. The purpose of this is to give an admin a heads up that their host is being probed.