also, it would be trivial to create a dns record that points to 127.0.0.1 or the ip of loadimpact.com, so you may want to blacklist things after resolving.
Yeah we have a restriction on number of started tests to the same hostname address, but it is actually more or less redundant as we have also several checks per IP address.
I might as well explain how it works as people seem to mention these things a lot here: when we know what URLs we have to load in order to load a web page (i.e. when we have generated a load script for the test) we find out all unique host addresses involved, then resolve the IP addresses to all these hosts, then we check how many times the last 24 hours we have performed tests where these IPs have been involved, how many bytes we have transferred from and to each of these IPs the last 24 hours, and how many transactions we have subjected these IPs to the last 24 hours. If any of these values exceed certain predefined tresholds, we deny the test.
