Unable to configure proxy with authentication for ML model download

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser):

Describe the issue:

Hi,

I’m trying to register ML models in OpenSearch, but my environment requires going through an HTTP proxy with authentication (user/password).

I’ve added JVM options like:

-Dhttp.proxyHost=xxx
-Dhttp.proxyPort=xxx
-Dhttp.proxyUser=xxx
-Dhttp.proxyPassword=xxx

-Dhttps.proxyHost=xxx
-Dhttps.proxyPort=xxx
-Dhttps.proxyUser=xxx
-Dhttps.proxyPassword=xxx

-Dhttp.auth.preference=basic

With curl, the proxy works fine (HTTP/2 200), but from OpenSearch I always get:

Unable to tunnel through proxy. Proxy returns “HTTP/1.1 407 authenticationrequired”

Has anyone successfully configured OpenSearch ML to work with a proxy requiring authentication?

Any guidance would be appreciated.

Thanks!

Configuration:

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