JVM parameter -Dhttp.nonProxyHosts is not honored.
As per debug logs it is seen that when proxy is configured, to connect to Portal OI is using proxy despite of adding portal host in JVM parameter -Dhttp.nonProxyHosts in java.conf.
OI Connector 3.23.0
The fix for this defect is currently targeted for DX NetOps 25.4.1 release (version 3.25.0 of the OI connector).