As part of my consulting business I have a number of web servers I take care of. This morning, I woke up to receive a particularly crappy message related to one of those servers: possible DoS attack Awesome, right? Ever notice how you never get these sorts of messages between the hours of 9 AM and 5 PM, Monday through Friday? So I tried to SSH into the target server, and was pleased to find I was able to connect. Relieved that this was likely a false alarm, I found this in the Apache logs: 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500] "GET /robots.txt HTTP/1.1" 200 146 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500] "GET /robots.txt HTTP/1.1" 200 146 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500] "GET /robots.txt HTTP/1.1" 200 146 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500] "GET /robots.txt HTTP/1.1" 403 5 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500] "GET /robots.txt HTTP/1.1" 403 5 40.77.167.20 - - [19/Jan/2016:19:43:15 -0500