count IPv4 connections per IP

netstat -anp |grep 'tcp\|udp' | awk '{print $5}' | sed s/::ffff:// | cut -d: -f1 | sort | uniq -c | sort -n
usefull in case of abuser/DoS attacks.
Sample Output

By: dt
2009-02-15 09:16:16

What Others Think

The netstat/grep/awk/sed is a bit much. You can cut it down to the following: netstat -nA inet |awk '/^[ut]/{print $5}'|cut -d: -f1 |sort |uniq -c |sort -n Better still if you don't mind a little bit more awk: netstat -nA inet |awk '/^[ut]/{split($5,a,":");print a[1]}'|sort |uniq -c |sort -n
hso · 638 weeks and 1 day ago
FWIW, you'll have to check your netstat syntax on other *nixes != Linux here, since -A inet is Linux specific (as is tcp/udp in $1).
hso · 638 weeks and 1 day 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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