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Graph # of connections for each hosts.

Terminal - Graph # of connections for each hosts.
netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
2009-04-27 22:02:19
User: knassery
Functions: awk grep netstat sort uniq
40
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Graph # of connections for each hosts.

Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate).

Show sample output | Add to favourites | Report as malicious

Know a better way?

If you can do better, submit your command here.

What others think

sexy...

Comment by jigglebilly 144 weeks and 4 days ago

Here's an interesting variation of this one that works with your routing cache:

route -Cn | grep eth0 | awk '{print $2}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }

Comment by thepicard 144 weeks and 4 days ago

You can make it a screensaver for your shell like this:

while(true); do sleep 5; clear; [YOURS]; done
Comment by ubersoldat 144 weeks and 3 days ago

Since 'awk' is a programming language (and uses associative arrays :-) ), you can shorten the expression like this:

netstat -4tn | awk -F'[\t :]+' '/ESTABLISHED/{hosts[$6]++} END{for(h in hosts){printf("%s\t%s\t",h,hosts[h]);for(i=0;i<hosts[h];i++){printf("*")};print ""}}'

Note that if you also have IPv6 connectivity, the code will get a little more complex.

Comment by chopinhauer 143 weeks and 6 days ago

some more ideas:

you could watch the output update every five seconds:

watch -n 5 $script

you could run this in a window within GNU screen:

screen -t WATCH watch -n 5 $script

you could make this a default window

by starting it within a screen session for root.

and you could make this session publically visible

for everyone on the one of the consoles (/dev/ttyN).

Comment by guckes 134 weeks and 2 days ago

this is why i love unix

Comment by firstohit 76 weeks and 1 day ago

Your point of view

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