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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.
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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Report the established connections for a particular port

Terminal - Report the established connections for a particular port
export PORT=11211; ss -an4 | grep -E "ESTAB.*$PORT" | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | sort -nr
2014-04-25 13:15:48
Functions: awk export grep sort uniq
Report the established connections for a particular port


There are 2 alternatives - vote for the best!

Terminal - Alternatives

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What others think

Hmm... first I tried to do this entirely in awk, but that got a bit complicated.

Instead, I've gone for replacing your "grep;awk;awk" with one "sed":

export PORT=11211; ss -an4 | sed -n '/ESTAB.*:'$PORT' .*:/{s/.* \([^:]\+\):.*:.*/\1/p}' | sort | uniq -c | sort -nr

It consists of three parts. A search:

'/ESTAB.*:'$PORT' .*:/

A replace:

s/.* \([^:]\+\):.*:.*/\1/

and print

sed -n ... p
Comment by flatcap 129 weeks and 6 days ago

this provides a very different report.

export PORT=11211; ss -an4 | grep -E "ESTAB.*$PORT" | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | sort -nr












export PORT=11211; ss -an4 | sed -n '/ESTAB.*:'$PORT' .*:/{s/.* \([^:]\+\):.*:.*/\1/p}' | sort | uniq -c | sort -nr


Comment by hornetmadness 129 weeks and 6 days ago

This is interesting. I had not yet played with "ss". I thought I could cut out some of the pipes to make it all faster while still using ss, but I couldn't. I did find a slightly different approach.

PORT=22 ; ss -n4 -o state established "( dport = :$PORT or sport = :$PORT )" | awk -F ':| +' '$1 ~ /[0-9]+/ {print $5}' | sort | uniq -c | sort -nr

I also noticed that when I had PORT=22 the 'grep -E "ESTAB.*$PORT"' also matched port 8022. It should probably at least be changed to:

grep -E "ESTAB.*:$PORT "

I also tried with lsof, but that was much slower:

PORT=ssh ; lsof -itcp:$PORT -stcp:established -n |awk -F '>|:| +' '$2 ~ /[0-9]+/ {print $11}' | sort | uniq -c | sort -rn
Comment by pdxdoughnut 129 weeks and 3 days ago

Your point of view

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