see what traffic is mostly hitting you

tcpdump -i eth0 -n | head
Sometimes it is useful to have just a general picture of "what is taking all the bandwidth here". Running this command will limit tcpdump to a few packets (instead of flooding your terminal endlessly) and will provide a small, but sometimes sufficient, sample to determine what is going on. Useful to quickly diagnose DOS attacks.

0
By: anarcat
2011-12-06 18:34:51

These Might Interest You

  • This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly: ssh root@example.com tcpdump -w - 'port !22' | wireshark -k -i -


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    ssh root@server.com 'tshark -f "port !22" -w -' | wireshark -k -i -
    markdrago · 2009-12-17 23:03:24 2
  • View all memcache traffic


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    sudo tcpdump -i eth0 -s 65535 -A -ttt port 11211
    kineticrick · 2011-03-10 08:20:00 0
  • Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses. Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.


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    tail -f /var/www/logs/domain.com.log | grep "POST /scripts/blog-post.php" | grep -v 192.168. | awk '{print $1}' | xargs -I{} iptables -I DDOS -s {} -j DROP
    tehusr · 2010-11-30 06:22:18 0
  • Run this on a windows machine then add your localhost as a socks server for port 8080 within your web browser. Your traffic will now be proxying and sent via your server over ssh.


    0
    Putty -d 8080 [server]
    felix001 · 2009-10-15 06:54:58 2

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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