La IP está oculta en el registro de apache para privacidad, excepto el último octeto. / facturación es nuestra página de inicio de la aplicación. Pero no tiene sentido que envíe solicitudes POST y obtenga 500 respuestas.
¿O quizás este es un navegador legítimo de IE 7 que no puede manejar nuestro sitio, ant sets al bucle?
Hay aproximadamente 20000 solicitudes de este tipo
xx.xx.xx.223 - - [30/May/2014:13:40:54 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:54 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:54 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:54 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:55 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:55 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:56 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:56 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:56 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:56 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:58 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:58 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:58 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"
xx.xx.xx.223 - - [30/May/2014:13:40:59 +0200] "POST /billing HTTP/1.1" 500 613 "-" "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.503l3; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MSOffice 12)"