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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.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

All IP connected to my host

Terminal - All IP connected to my host
netstat -lantp | grep ESTABLISHED |awk '{print $5}' | awk -F: '{print $1}' | sort -u
2011-07-21 21:23:10
User: bitbasher
Functions: awk grep netstat sort
All IP connected to my host

find all computer connected to my host through TCP connection.


There is 1 alternative - vote for the best!

Terminal - Alternatives
netstat -nut | sed '/ESTABLISHED/!d;s/.*[\t ]\+\(.*\):.*/\1/' | sort -u
netstat -nut | awk '$NF=="ESTABLISHED" {print $5}' | cut -d: -f1 | sort -u
2011-07-27 07:24:10
User: bitbasher
Functions: awk cut netstat sort

find all computer connected to my host through TCP connection

Know a better way?

If you can do better, submit your command here.

What others think

Does not support IPv6. Returns first segment of address only.

[email protected]:~# netstat -lantp | grep ESTABLISHED |awk '{print $5}' | awk -F: '{print $1}' | sort -u


Comment by unixmonkey23784 274 weeks ago

unixmonkey23784 --> Is it ok now (Don't have ipv6)

# netstat -lantp | grep ESTABLISHED |awk '{print $5}' | awk '{print $1}' | sort -u

(with ipv4, also display port due to the lack of "-F :")

Hope it will be helpfull... First contribution ...

Comment by n3wborn 274 weeks ago

Options -l, -p and -a are useless in this netstat call. This command also misses *all* udp connections.

Full list, sorted as in original post, would be given by: netstat -nut | awk '$NF=="ESTABLISHED" {print $5}' | cut -d: -f1 | sort -u

Comment by depesz 274 weeks ago

it is inefficient to pipe awk to awk.

Comment by Mozai 274 weeks ago

sudo netstat -nut | sed '/ESTABLISHED/!d;s/.*[\t ]\+\(.*\):.*/\1/'

Comment by plasticdoc 273 weeks and 5 days ago

shorter (thanks to the help of e36freak on freenode for the + sign that I missed) :

netstat -nut | awk -F'[ :]+' '/SHED *$/{print $6}'
Comment by sputnick 272 weeks and 3 days ago

Your point of view

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