dropped packets with reverse proxy app

[thomas.sec]

Hello,

We are experiencing connection drops when making requests to web services while OPNsense is configured as a reverse proxy (same behavior with both Nginx and Caddy).

Example log entry:

Code Select Expand

"GET /uri?param=x HTTP/1.1" 499 0 "-" "User-Agent" 30.028 30.028
The reported time is always very close to 30 seconds.

We do not experience packet loss when OPNsense is configured with direct port forwarding to the web server.

Could there be a timeout parameter in the reverse proxy configuration that we have missed? We find it unusual that this behavior is the same with both Nginx and Caddy.

We have also tried adjusting the "conservative" mode and bypassing rules on the same interface, but without success.

Thank you in advance for your help.

Best regards,
Thomas

[Monviech (Cedrik)]

Could you find out where exactly the packets are dropped on their path?

Trace the full forward and return path and identify the exact spot where the packet gets lost.

If the behavior is the same for any reverse proxy, I suspect its the http client inside the reverse proxy that communicates with the webserver. So most likely the served backend webserver needs some configuration adjustments here.