netstat is a network utility that displays a variety of statistics for network connections on a system. It displays incoming and outgoing connections, routing tables, and a number of other network statistics. Under Linux, it is considered deprecated, and you are advised to use dss instead (part of the iproute2 package), although netstat may still work, depending on which distribution you are using.
netstat, without any command-line arguments, will display a list of active sockets for each network protocol. If you invoke netstat under Linux, it will also display a list of active Unix domain sockets. There are several columns of output. Proto stands for protocol, with a 6 in the column denoting use of IPv6. Recv-Q tells you how many ...