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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

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Commands tagged netstat from sorted by
Terminal - Commands tagged netstat - 47 results
netstat -ntu | awk ' $5 ~ /^[0-9]/ {print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
watch 'netstat -anptu |egrep "^Proto|:80 "'
2011-05-18 15:05:52
User: Mozai
Functions: egrep watch

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".

while sleep 1; do date; (netstat -a -n | grep 80) ; done
netstat -rn | awk '/UG/{print $2}'
2010-08-09 15:56:02
User: putnamhill
Functions: awk netstat

Tested on CentOS, Ubuntu, and MacOS.

netstat -rn | grep UG | tr -s " " | cut -d" " -f2
netstat -l -p --tcp | egrep -e 'www.*[0-9]{3,4}\/(apache2|httpd)' | awk '{print$7}'
lsof -Pan -i tcp -i udp
2010-06-07 15:22:44
User: atoponce
Tags: netstat lsof

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.

netstat -tunlp
2010-06-07 13:26:05
User: ender_x
Functions: netstat
Tags: netstat

Shows you all listening tcp/udp ports, and what program has them open(depending on rights)

netstat -an | awk '/tcp/ {print $6}' | sort | uniq -c
2010-05-06 17:04:37
User: Kered557
Functions: awk netstat sort uniq

Counts TCP states from Netstat and displays in an ordered list.

netstat -in
netstat -ltun
2009-10-05 08:39:03
User: Decoy
Functions: netstat

Works only on Linux.

Last option (n) turn name of service resolving (/etc/services) off.

ss -p
2009-09-19 21:55:01
User: Escher

for one line per process:

ss -p | cat

for established sockets only:

ss -p | grep STA

for just process names:

ss -p | cut -f2 -sd\"


ss -p | grep STA | cut -f2 -d\"
netstat -lantp | grep -i stab | awk -F/ '{print $2}' | sort | uniq
2009-09-19 14:54:31
User: ProMole
Functions: awk grep netstat sort

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")

netstat -lantp | grep -i establ | awk -F/ '{print $2}' | sort | uniq
netstat -lantp | grep -i establ | awk -F/ '{print $2}' | uniq | sort
2009-09-19 13:54:36
User: ktoso
Functions: awk grep netstat uniq

Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.

Has anyone an idea why the uniq doesn't work propperly here (see sample output)?

netstat -lnp
kill_daemon() { echo "Daemon?"; read dm; kill -15 $(netstat -atulpe | grep $dm | cut -d '/' -f1 | awk '{print $9}') }; alias kd='kill_daemon
2009-05-26 20:39:56
User: P17

Just find out the daemon with $ netstat -atulpe. Then type in his name and he gets the SIGTERM.

netstat -taupe
2009-05-25 12:46:38
User: farwarx
Functions: netstat

Affiche des infos detaillees sur vos connexions reseaux.

Port en ?coute, protocole, paquets, adresses, ustilisateur, PID etc...

p=$(netstat -nate 2>/dev/null | awk '/LISTEN/ {gsub (/.*:/, "", $4); if ($4 == "4444") {print $8}}'); for i in $(ls /proc/|grep "^[1-9]"); do [[ $(ls -l /proc/$i/fd/|grep socket|sed -e 's|.*\[\(.*\)\]|\1|'|grep $p) ]] && cat /proc/$i/cmdline && echo; done
2009-04-30 12:39:48
User: j0rn
Functions: awk cat grep ls netstat sed

Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all...

At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p

It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc

So for a specific port, this line returns the calling command line of every thread that handle the associated socket

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

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
netstat -alpn | grep :80 | awk '{print $4}' |awk -F: '{print $(NF-1)}' |sort | uniq -c | sort -n