Cloudflare DNS Breaks PRTG UI

Did you configure the DNS name in PRTG accordingly (Setup | System Administration | User Interface)?

Kind regards,
Stephan Linke, Tech Support Team

Yes, the DNS name is set correctly.

While we have little to no customers using cloudflare with PRTG - what URL do you get redirected to after the login?

Kind regards,
Stephan Linke, Tech Support Team

I get redirected to "https://prtg.ourdomain.com/welcome.htm" after I login.

Is there anything in the browser console that hints on what exactly the problem could be? Anything in PRTGs webserver logs located in the data directory? You could also provide us a support bundle via Setup | Contact Support so we could check it. Adding cloudflare beforehand and triggering the issue will help finding it in the log files.

Kind regards,
Stephan Linke, Tech Support Team

I have submitted a support bundle. The webserver logs only show "GET" requests for the items I click on. My browser console only displays the following:

unreachable code after return statement [Learn More] rocket.min.js:3863:111 unreachable code after return statement [Learn More] rocket.min.js:27627:65 unreachable code after return statement [Learn More] rocket.min.js%20line%204%20%3E%20eval:3863:111 window.controllers/Controllers is deprecated. Do not use it for UA detection. rocket.min.js%20line%204%20%3E%20eval:28222:417 unreachable code after return statement [Learn More] rocket.min.js%20line%204%20%3E%20eval:27627:65

From the errors you get, it actually seems that cloudflare isn't able to process PRTG's JavaScript.

I kindly ask you to submit another Support Bundle, somehow I cannot find the previous one. Please refer to the case "PAE1005001" when submitting the bundle.

Thank you!

Best regards,
Andreas Günther, Tech Support Team

Hi,

I also have a similar problem using Cloudflare, but most page rendered correctly, except some element, especially at 'Device -> All' page where the inventory explorer window is not appeared. I have to resort to 'Device -> List' to view the item, but then I still stuck if I want to add more devices.

Any update on this matters?

Hello,

Thank you for your message.

I'm afraid that there is no information regarding that issue, therefore I invite you to check the developer console, network tab as well as webserver logs (by default located under "C:\ProgramData\Paessler\PRTG Network Monitor\Logs\webserver") while navigating on the affected pages in PRTG. This could provide you indications on its origin.

Please, make sure that there is no addons which could affect the web interface.

As troubleshooting can be more complicated in the knowledge base, you can also provide us as support bundle (Setup > Contact Support) if you haven't found any indications for the issue.

Regards.

Hi all,

I managed to solved this!

Somehow Cloudflare auto-minify for HTML components doesn't play nice with PRTG. So what i did was:

either you just enable auto-minify for JS and CSS but not for HTML in global settings or set new Rules for that particular PRTG url to auto-minify JS and CSS but not HTML

Mine is working.

Hi,

Thank you for sharing the solution. It will definitely help other PRTG user in the same situation.

Our colleague Jasmin redacted an article on his blog about it as well (to share this information): https://techwithjasmin.com/monitoring/cloudflare-how-to-fix-the-prtg-device-tree-not-loading/

Have a great day.