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Probe connections behind a reverse proxy

Votes:

0

Hi everyone,

I've been trying to get a test prtg server working in Azure behind an Application Gateway. After following the guides it was easy to get the website working behind the proxy, but the probe doesn't seem to connect.

It seems that the probes always connect via a TLS connection, so I've set the backend connection to be an HTTPS one. I've also disabled SNI for the probe connection as it doesn't seem to need it, but again, not sure.

Has anyone been able to get the core server probe port available via a reverse proxy?

This is what the logs show on the core PRTG server:

22-8-2016 21:37:52 Start Connection
22-8-2016 21:37:52 Start Done
22-8-2016 21:37:57 Connect from  to 23.45.67.89:23560
22-8-2016 21:37:57 TCP connected from 10.0.0.10:54990 to 23.45.67.89:23560
22-8-2016 21:37:57 State changed to connected (23.45.67.89:23560)
22-8-2016 21:37:58 Connected
22-8-2016 21:38:03 State changed to disconnected (23.45.67.89:23560)
22-8-2016 21:38:08 Connect from  to 23.45.67.89:23560
22-8-2016 21:38:08 Client Connection: Already connected.
22-8-2016 21:38:08 Send Login
22-8-2016 21:38:18 Try to Create new Connection
22-8-2016 21:38:28 Create new Connection
22-8-2016 21:38:38 Connect from  to 23.45.67.89:23560
22-8-2016 21:38:38 TCP connected from 10.0.0.10:54991 to 23.45.67.89:23560
22-8-2016 21:38:38 State changed to connected (23.45.67.89:23560)
22-8-2016 21:38:39 Connected
22-8-2016 21:38:39 Send Login
22-8-2016 21:38:39 State changed to disconnected (23.45.67.89:23560)
22-8-2016 21:38:44 Connect from  to 23.45.67.89:23560
22-8-2016 21:38:44 Client Connection: Already connected.
22-8-2016 21:38:54 Try to Create new Connection
22-8-2016 21:39:04 Create new Connection

application-gateway azure probe reverse-proxy ssl-offload

Created on Aug 22, 2016 7:49:32 PM

Last change on Aug 23, 2016 7:51:05 AM by Torsten Lindner [Paessler Support]



1 Reply

Votes:

0

Hello,

The log shows constant connection attempts by the probe. PRTG does not know the cause of the disconnection, hence the lack of a more detailed log entry. Something, perhaps a firewall, is interfering, and closes the connection. Please make sure to allow TCP port 23560 being used for the probe-core connection. You have to set a exception for the probe-core connection for the reverse proxy.

Created on Aug 23, 2016 3:15:47 PM by [email protected]

Last change on Aug 23, 2016 3:17:53 PM by [email protected]




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