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The HTTP Content Sensor returns a error



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In meiner Konfiguration verwende ich den Sensor HTTP(Inhalt). Auf einer Webseite mit HTTPS und Authentifizierung habe ich das Beispiel: <html> <body> Description: Script gives back current status of disk free (%) and CPU usage (%). [85.5][12.0] </body> </html> in die Datei status.html geschrieben.

Den Sensor habe ich mit Wertyp Fließkomma und 2 Kanäle konfiguriert. Die Authentifizierungsdaten habe ich übergeben.

Beim Aufruf des Sensor erhalte ich immer die Fehlermeldung:

Unexpected Format CDATA[ var theForm = document.forms['Form1'

Beste grüße


In my configuration I use the sensor HTTP Content Sensor. On a website with HTTPS and authentication I have the Example <html> <html> <body> Description: Script gives back current status of disk free (%) and CPU usage (%). [85.5][12.0] </body> </html> written to the file status.html.

I have onfigured the sensor with Value Type float and 2 channels. I have transferred the authentication data.

When calling the sensor I always get the error message:

Unexpected Format CDATA[ var theForm = document.forms['Form1''

best regards

http-content-sensor prtg unexpected-format

Created on Sep 21, 2018 8:40:47 AM by  HHZujg (0) 1

2 Replies



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it's obvious that the web server reply includes a cdata section in the body, however in the Original Poster (OP) quoted html snippet there is none. So it seems that the web server used is probably more than a vanilla web server that spits out html stored in a disk file, rather more something like a CMS where a html snippet provided by the CMS user is massaged through an elaborate machinery to conform to the general site design.

In my opinion the OP should have provided a dump of the web server reply (using the PRTG function Advanced Sensor Data / write sensor result to disk) to get a better diagnostic, But of course it's a bit late to ask for that.

If there is a problem in PRTG, it may be that it does not test for the CDATA case, not allowing complex web sites to work easily with the HTTP Content sensor.

Created on Oct 16, 2018 9:34:07 PM by  gpfr (60) 1 1



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Hello gpfr,

Thank you very much for your response.

Indeed, your assumption is valid. Using the 'Write Results to Disk' option within the sensor's settings tab is a good approach. What you couldn't know is that I contacted the OP directly via email in regards to this request, unfortunately I didn't receive a response there too.

So, we'll see if this goes on but thank you for your contribution too.

Best regards,

Created on Oct 17, 2018 6:19:39 AM by  Sebastian Kniege [Paessler Support]

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