The netstat command is used to display active network connections on your workstation or server. Netstat can be used to display active TCP connections, ports on which the computers is listening, ethernet statistics, the IP routing table, IPv4 and IPv6 statistics. Used without parameters, netstat display active TCP connections.
Syntax
netstat [-a] [-e] [-n] [-o] [-p <em>Protocol</em>] [-r] [-s] [<em>Interval</em>]
Parameters
-a : Displays all active TCP connections and the TCP and UDP ports on which the computer is listening
-e : Displays ethernet statistics, such as the number of bytes and packets sent and received. This parameter can be combined with -s
-n : Displays active TCP connections, however, addresses and port numbers are expressed numerically and no attempt is made to determine names
-o : Displays active TCP connections and includes the process ID (PID) for each connection. You can find the application based on the PID on the processes tab in Windows Task Manager. This parameter can be combined with -a, -n, and -p.
-p Protocol : Shows connections for the protocol specified by Protocol. In this case, the Protocol can be tcp, udp, tcpv6, or udpv6. If this parameter is used with -s to display statistics by protocol, Protocol can be tcp, udp, icmp, ip, tcpv6, udpv6, icmpv6, or ipv6.
-s : Displays statistics by protocol. By default, statistics are shown for the TCP, UDP, ICMP, and IP Protocols.
-r : Displays the contents of the IP routing table. This is equivalent to the route print command.
Interval : Redisplays the selected information every Interval seconds. Press Ctrl + C to stop the redisplay. If this parameter is omitted, netstat prints the selected information only once.
/? : Displays help at the command prompt.
Examples
coming soon…
Alternatives
TCPView from SysInternals is another nice utility that takes netstat one step further. With TCPView you can view the active process name as well.
http://technet.microsoft.com/en-us/sysinternals/bb897437.aspx
