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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
2
Report the established connections for a particular port

Alternatives

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 21 weeks and 4 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

34 10.1.1.184

33 10.1.1.187

33 10.1.1.181

32 10.1.1.178

31 10.1.1.183

30 10.1.1.199

29 10.1.1.179

28 10.1.1.182

27 10.1.1.185

26 10.1.1.186

4 10.1.1.189

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

256 10.1.1.190

Comment by hornetmadness 21 weeks and 4 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 21 weeks ago

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