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
[[email protected] root]# netstat -ntu | awk '{print $5}' |  cut -d: -f1 | sort | uniq -c | sort -n | tail           
      8	200.217.193.102
      8	82.101.189.139
      9	84.195.188.60
     11	189.63.98.3
     11	60.28.166.169
     13	24.227.166.150
     15	200.214.44.134
     16	189.92.141.77
     22	189.14.101.44
     31	127.0.0.1

2
By: TuxOtaku
2009-02-16 15:48:27

What Others Think

I have just analyzed your written command for the Netstat Connection Check and has found it useful. It would be good to buy a speech online for help in representation. Your suggested command is totally functional on my system and it is running smoothly.
CharlotteAdams · 6 weeks and 6 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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