Command for viewing port usage in GNU/Linux

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/*************************************** ******************************
* Author: Samson
* Date: 04/08/2014
* Test platform:
* Linux debian-IDS 3.13.7
* GNU bash, version 4.2.37
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Method 1:

Root @ debian:/home/# netstat-ant
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
Tcp 0 0 127.0.0.1: 25 0.0.0.0: * LISTEN
Tcp 0 0 0.0.0.0: 33223 0.0.0.0: * LISTEN
Tcp 0 0 127.0.0.1: 3306 0.0.0.0: * LISTEN
Tcp 0 0 0.0.0.0: 111 0.0.0.0: * LISTEN
Tcp6 0 0: 1: 25: * LISTEN
Tcp6 0 0: 60042: * LISTEN
Tcp6 0 0: 111: * LISTEN
Tcp6 0 0: 80: * LISTEN
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1119 ESTABLISHED
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1123 ESTABLISHED
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1125 TIME_WAIT
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1112 TIME_WAIT
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1110 TIME_WAIT
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1122 ESTABLISHED
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1114 TIME_WAIT
Tcp6 0 0 111.111.111.120: 80 111.111.111.114: 1117 TIME_WAIT

Method 2:

Root @ debian:/home # lsof-I: 80
Command pid user fd type device size/OFF NODE NAME
Apache2 2301 root 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 2497 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 2498 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 2499 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 2500 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 2501 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 6108 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 6117 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)
Apache2 6118 www-data 4u IPv6 7298 0t0 TCP *: http (LISTEN)

// Mysql default port

Root @ debian:/home # lsof-I: 3306
Command pid user fd type device size/OFF NODE NAME
Mysqld 2992 mysql 10u IPv4 9546 0t0 TCP localhost: mysql (LISTEN)