Commands matching netstat (158)

  • Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate). Show Sample Output


    52
    netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
    knassery · 2009-04-27 22:02:19 7
  • This command is more portable than it's cousin netstat. It works well on all the BSDs, GNU/Linux, AIX and Mac OS X. You won't find lsof by default on Solaris or HPUX by default, but packages exist around the web for installation, if needed, and the command works as shown. This is the most portable command I can find that lists listening ports and their associated pid. Show Sample Output


    29
    lsof -Pan -i tcp -i udp
    atoponce · 2010-06-07 15:22:44 0

  • 25
    netstat -ant | awk '{print $NF}' | grep -v '[a-z]' | sort | uniq -c
    himynameisthor · 2009-02-05 18:02:59 4
  • Command binds a set of commands to the F12 key. Feel free to alter the dashboard according to your own needs. How to find the key codes? Type read Then press the desired key (example: F5) ^[[15~ Try bind '"\e[15~"':"\"ssh su@ip-address\C-m""" or bind '"\e[16~"':"\"apachectl -k restart\C-m""" Show Sample Output


    18
    bind '"\e[24~"':"\"ps -elF;df -h;free -mt;netstat -lnpt;who -a\C-m"""
    Neo23x0 · 2009-06-21 23:57:20 5
  • It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here. Show Sample Output


    18
    watch "netstat -plan|grep :80|awk {'print \$5'} | cut -d: -f 1 | sort | uniq -c | sort -nk 1"
    ik_5 · 2010-03-15 09:27:43 2
  • Particularly useful on OS X where netstat doesn't have -p option. Show Sample Output


    18
    lsof -i -P | grep -i "listen"
    patko · 2010-10-14 09:37:51 3
  • find all computer connected to my host through TCP connection. Show Sample Output


    16
    netstat -lantp | grep ESTABLISHED |awk '{print $5}' | awk -F: '{print $1}' | sort -u
    bitbasher · 2011-07-21 21:23:10 6
  • -p Tell me the name of the program and it's PID -l that is listening -u on a UDP port. -n Give me numeric IP addresses (don't resolve them) -t oh, also TCP ports Show Sample Output


    15
    netstat -plunt
    JamesGreenhalgh · 2009-02-06 06:04:32 2
  • Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount. BSD Version: netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr Show Sample Output


    14
    netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
    tiagofischer · 2009-03-28 21:02:26 4

  • 14
    watch -n 1 "netstat -tpanl | grep ESTABLISHED"
    klipz · 2009-04-13 20:40:41 4
  • usefull in case of abuser/DoS attacks. Show Sample Output


    12
    netstat -anp |grep 'tcp\|udp' | awk '{print $5}' | sed s/::ffff:// | cut -d: -f1 | sort | uniq -c | sort -n
    dt · 2009-02-15 09:16:16 2
  • credit to tumblr engineering blog @ http://engineering.tumblr.com/ Show Sample Output


    8
    netstat -tn | awk 'NR>2 {print $6}' | sort | uniq -c | sort -rn
    evandrix · 2011-09-12 23:29:39 0
  • While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own) Show Sample Output


    8
    netstat -plnt
    DopeGhoti · 2011-09-30 19:56:32 0
  • See connection's tcp timers Show Sample Output


    8
    netstat -town
    ioggstream · 2012-10-08 13:10:04 0
  • This is a very powerful command line tool to gather statistics for a Linux system. http://dag.wieers.com/home-made/dstat/ Show Sample Output


    7
    dstat -ta
    vutcovici · 2009-04-02 14:19:12 1
  • Show apps that use internet connection at the moment. Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes. This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO") Show Sample Output


    7
    netstat -lantp | grep -i stab | awk -F/ '{print $2}' | sort | uniq
    ProMole · 2009-09-19 14:54:31 0
  • see the TIME_WAIT and ESTABLISHED nums of the network Show Sample Output


    7
    netstat -n | awk '/^tcp/ {++B[$NF]} END {for(a in B) print a, B[a]}'
    healthly · 2010-04-24 12:11:52 0
  • Displays a connection histogram of active tcp connections. Works even better under an alias. Thanks @Areis1 for sharing this one.


    7
    netstat -an | grep ESTABLISHED | awk '\''{print $5}'\'' | awk -F: '\''{print $1}'\'' | sort | uniq -c | awk '\''{ printf("%s\t%s\t",$2,$1); for (i = 0; i < $1; i++) {printf("*")}; print ""}'\''
    mramos · 2010-07-09 00:25:45 2
  • Shows updated status in a terminal window for connections to port '80' in a human-friendly form. Use 'watch -n1' to update every second, and 'watch -d' to highlight changes between updates. If you wish for status updates on a port other than '80', always remember to put a space afterwards so that ":80" will not match ":8080". Show Sample Output


    7
    watch 'netstat -anptu |egrep "^Proto|:80 "'
    Mozai · 2011-05-18 15:05:52 4
  • -p PID and name of the program -u on a UDP port. -t also TCP ports -o networking timer -n numeric IP addresses (don't resolve them) -a all sockets


    6
    netstat -putona
    starchox · 2009-02-16 19:14:35 4

  • 6
    netstat -ntauple
    luqmanux · 2009-07-02 20:18:26 2
  • The -W switch of netstat makes it print complete URL of the connections, which otherwise by default is truncated to fit its default column size. Now to compensate for irregular column sizes, pipe the output to column (-t switch of column prints in tabular form). The only downside to this part is that the very first row, the header, goes pear shape. Show Sample Output


    6
    netstat -tup -W | column -t
    b_t · 2014-01-08 22:39:01 0
  • I often have to google this so I put it here for quick reference.


    6
    netstat -np | grep -v ^unix
    UnklAdM · 2015-11-09 17:22:30 3
  • Uses lsof to list open network connections (file descriptors), grepping for only those in an established state


    5
    lsof -i -n | grep ESTABLISHED
    systemj · 2009-02-05 15:28:11 0
  • Alternative: ss -tlpn Show Sample Output


    5
    netstat -tlpn
    maxo · 2019-03-21 07:51:20 2
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