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Configuration tips for HTTP Transaction sensors needed



I need additional information on how to set up an HTTP Transaction sensor, especially on how to find out the correct POSTDATA settings.

cookie http http-sensor login postdata recorder sensor transaction url webserver-sensor

Created on Feb 3, 2010 12:37:42 PM by  Roland Grau [Paessler Support]

Last change on Dec 4, 2020 1:45:11 PM by  Brandy Greger [Paessler Support]

5 Replies

Accepted Answer



This article applies as of PRTG 22

The HTTP Transaction sensor - tips and tricks

With the the HTTP Transaction sensor, you can monitor a sequence of URLs on a web server. This is useful, for example, to ensure that placing products into a shopping cart and then passing the checkout actually works.

A word of caution

For some web applications, it can be quite complicated if not impossible to create an HTTP Transaction sensor in PRTG.

The HTTP Transaction sensor requires your web application to use cookies for session management. If your web application uses hidden fields, URL parameters, POST fields, JavaScript (or other methods that require interaction with a real browser) to store session id(s), you cannot monitor it with the HTTP Transaction sensor.

Be aware that our support team cannot take over the duty of creating and debugging the HTTP Transaction sensor settings for you and your website. However, the sensor is already in use on many different websites and can be considered reliable.

What you need

The HTTP Transaction sensor simulates the HTTP requests that are sent to a server by a user visiting a sequence of web pages (while preserving the cookies during all requests).

To simulate this, you must give the URLs and their POSTDATA (for POST requests only) to the HTTP Transaction sensor. Simply copy the URLs from the URL edit field of your web browser. To get the POSTDATA, see the steps below:

Getting POSTDATA via developer tools

You can get the POSTDATA in a few mouse clicks with your web browser's developer tools. They help you to find out the URLs and the POSTDATA strings that are send to a web server while visiting a sequence of URLs.

How to open developer tools in Chrome

  • Go to Options | More Tools | Developer tools or via the Windows shortcut Control+Shift+I.
  • Go to the Network tab.

How to open developer tools In Firefox

  • Go to Options | More tools | Web Developer Tools | or via the Windows shortcut Control+Shift+I.
  • Go to the Network tab.

Note: In both Chrome and Firefox, you can also right-click an element and inspect it to open the developer tools.

  • In the browser window, use the mouse to go through the URL sequence you want to record. While you access each page, the URL and - if you submit a POST request - the POSTDATA is stored in the list of the developer tools console.
  • Stop the recording when you reach the last web page of your URL sequence.
  • When you are done, you can use the URL list's context menu to copy or save URLs or POSTDATA.

Note: For more information on the developer tools options, see your browser's website.

Transferring the data to PRTG

  1. Open the PRTG web interface.
  2. Create a new HTTP Transaction sensor and copy the URLs (and for POST requests, the POSTDATA) with the information from the developer tools into the sensor settings.
  3. Check the other settings of the sensor and submit the page.

You should now be able to monitor the sequence as desired.

Important notice: Be aware that if the sequence you recorded was a shopping cart or any other transactional activity, PRTG now causes the same purchase or transaction every few minutes if you do not prevent this.

Created on Feb 3, 2010 12:39:32 PM by  Roland Grau [Paessler Support]

Last change on Jan 3, 2023 8:13:04 AM by  Brandy Greger [Paessler Support]



Disappointing help.

Created on Jun 1, 2018 12:27:12 AM




How can we be of assistance?

Benjamin Day
[Paessler Support]

Created on Jun 1, 2018 12:44:18 AM by  Benjamin Day [Paessler Support] (1,441) 2 1



" If your web application uses hidden fields, URL parameters, POST fields, Javascript (or other methods that require interaction with a real browser) to store session id(s), then you can not monitor it using the HTTP Transaction sensor."

How about stating which sensor type would be available to monitor webpages that use javascript to store session id(s)?

Created on Aug 20, 2018 3:00:03 PM




That would require some special coding, as PRTG does not have sensors that work with those elements out of the box.

Benjamin Day
Paessler Support

Created on Aug 21, 2018 8:40:21 PM by  Benjamin Day [Paessler Support] (1,441) 2 1

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.