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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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Show number of connections per remote IP

Terminal - Show number of connections per remote IP
netstat -antu | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | sort -n
2013-04-08 19:46:41
User: wejn
Functions: awk netstat sort uniq
Show number of connections per remote IP

Output contains also garbage (text parts from netstat's output) but it's good enough for quick check who's overloading your server.


There are 6 alternatives - vote for the best!

Terminal - Alternatives
netstat -antu | awk '$5 ~ /[0-9]:/{split($5, a, ":"); ips[a[1]]++} END {for (ip in ips) print ips[ip], ip | "sort -k1 -nr"}'

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What others think

Too much pipe for be a cmd-line fu...

Comment by Zulu 262 weeks and 4 days ago

Note that with the above syntax you'll return 'Address' and 'and' in the results. Also, the use of netstat, and other commands from 'net-tools' should be considered depreciated:

awk '{gsub(/dst=/,"") ; print $6}' /dev/null)

Comment by khayyam 262 weeks and 2 days ago

oh, surprise, another command munged by the content management system.

Comment by khayyam 262 weeks and 2 days ago

@khayyam care to explain what else to use besides net-tools? I know I could parse /proc/net/tcp but that hardly seems appropriate.

Comment by wejn 262 weeks and 2 days ago

Your point of view

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