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# Here a few bash one-liners that helped me analyze / fight a weak DOS attack against debuggable.com. Mostly for future reference. | |
# The attacker was opening lots of tcp connections without sending data, I believe it's called a SYN flood, see: http://tools.ietf.org/html/rfc4987#section-3.2 | |
# Step 0: Check what is going on at port 80 | |
$ netstat -tan | grep ':80 ' | awk '{print $6}' | sort | uniq -c | |
# Step 1: Increase the number of available fds | |
$ ulimit -n 32000 | |
# Step 2: Restart your webserver, for me: |