How to find out Active Connections or which Ports are open/listening on Linux

view story

http://linuxers.org – While managing a server or your home desktop, sometimes you might want to check out which ports are currently being used by which applications, what all TCP/UDP connections are active at the moment or other similar cases. There are two basic command line tools present in almost all the Linux/UNIX based systems - netstat and lsof, that might help you out with such queries. Before starting it would be good to know about these two commands. Netstat is used to display network connections, routing tables and a whole bunch of network and interface st (General)