Entry Level 게시물

How to list the ports a Linux server is listening on with ss and lsof, read the output, and decide which services should not be exposed.

Ever wondered about the systems that keep the lights on? Most of us rarely think about the infrastructure that makes modern life possible. We flip a switch and expect electricity, turn on a tap and expect clean water, and rely on transportation, manufacturing, and energy systems to operate around the clock. Behind the scenes, a vast network of industrial technologies works continuously to keep these essential services running. These systems are collectively known as Industrial Control Systems (ICS) and form the backbone of much of the world’s critical infrastructure.