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Some links wrong when using HAProxy for external access



I'm using HAProxy to proxy web access to the PRTG web interface from external locations and for the most part it works well. However in many places the URL is wrong with the internal port still being used. E.g. my external FQDN is https://prtg.mydomain.com and it is forwarded by HAProxy to internalIP:8081

When I perform an upgrade, the notification screen that appears shows and monitors https://prtg.mydomain.com:8081 which doesn't work, the same with the notification emails, all it's links get the the port 8081 appended.

The main website works very well for 99% of the time, and even the Android app has no problems. Just the areas I mention above and probably more suffer this issue. Internally of course using port 8081 is fine, but I am not going to expose this directly to the internet. HAProxy proxies for 6 other internal applications just fine although one or two needed tweaks.

Is there any way to fix this for PRTG?

haproxy reverse-proxy web-interface

Created on Sep 16, 2019 8:20:29 AM

4 Replies



Dear Customer,

Please check the entered DNS Name in the User Interface menu. You can access this menu via Setup | System Administration | User Interface.
It could be possible that you have entered the Port :8081 into the DNS-Name. If so, I would ask you to remove the port and test if the problem persists.

Kind regards,
Marijan Horsky, Tech Support Team

Created on Sep 16, 2019 11:59:52 AM by  Marijan Horsky [Paessler Support]



The DNS name is just the external FQDN that I use to access it from the Internet - the 8081 is being added elsewhere.

Created on Sep 16, 2019 2:06:11 PM



Hi Ferd,

PRTG generates the links independently and passes them on with DNS name and port, because PRTG basically doesn't know anything about a proxy. These links cannot be changed by a proxy or through PRTG.

Best regards.

Created on Sep 17, 2019 9:59:45 AM by  Marijan Horsky [Paessler Support]



Ok, so any chance you can feature request this as an option for a future release?

But what about the screen when upgrading? That's the website and the rest of the website is generating the correct URL from the incoming FQDN namely my external one when outside and the internal one when inside.

Created on Sep 17, 2019 10:07:24 AM

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