Proxy Error in java splunk query

[jimdiconectiv]

We are developing an internal Splunk Java SDK application that is well along but
in moving it from test space, a laptop that can reach the internet, to linux servers in prod test space
we pick up an odd error message from the Java SDK below:
"Encountered Throwable in splunkQuery Unable to tunnel through proxy. Proxy returns "HTTP/1.1 403 Forbidden""

We have configured no proxy in the sdk or the splunk instance.

This only happens on the SDK location that cannot reach the internet and has no proxy set up, the
same query and system of queries works fine from the desktop.

I have set up: NO_PROXY="127.0.0.1,localhost,[::1]" in splunk-launch.conf on the splunk server,
But this has not helped.

Our management is super concerned to get this going. Can you help with what proxy is being
called and how to stop this.

Calls to Splunk via curl work from this server.

[jimdiconectiv · Accepted solution]

There was a real proxy in line configurd in Java and the proxy rejected the call. This was difficult to trace.