Netstat Connection Check

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n | tail
This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.
Sample Output
[root@vps10 root]# netstat -ntu | awk '{print $5}' |  cut -d: -f1 | sort | uniq -c | sort -n | tail           

By: TuxOtaku
2009-02-16 15:48:27

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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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