Software >> OS >> Unix >> Linux >> How to use lsof to check process owning a TCP/UDP port

To check specific port ====================== # lsof -i tcp:<portno> to display hostnames or # lsof -ni tcp:<portno> to display IP address only To check all ports ================== # lsof -ni udp # lsof -ni tcp To check a specific IP or hostname and port =========================================== # lsof -ni [protocol][@hostname|hostaddr][:service|port] To list open files (file descriptors) by a process ================================================== # lsof -p <pid>