My apache2 log is bombarded with lines like: 108.5.114.118 - - [03/Aug/2012:15:23:28 +0200] "GET http://xchecker.net/tmp_proxy2012/http/engine.php HTTP/1.0" 404 1690 "http://xchecker.net/tmp_proxy2012/http/engine.php" "Mozilla/4.0 (compatible; MSIE 6.0; Windows 98; Win 9x 4.90)" I am puzzled by this -- why is a request for some weird xchecker.net domain ending up on my server in the first place?! The request comes every few dozens of seconds, must be a robot. Any ideas what it is? Btw that URL is valid -- apparently it contains some test page...