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 "" }'
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).
Sample Output	3	***   5       *****

By: knassery
2009-04-27 22:02:19

What Others Think

jigglebilly · 628 weeks and 6 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 "" }
thepicard · 628 weeks and 6 days ago
You can make it a screensaver for your shell like this: while(true); do sleep 5; clear; [YOURS]; done
ubersoldat · 628 weeks and 6 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.
chopinhauer · 628 weeks and 2 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).
guckes · 618 weeks and 4 days ago
this is why i love unix
firstohit · 560 weeks and 3 days ago
noqqe · 475 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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