Kubernetes Credentials Provider plugin does not respect 'no_proxy' Java property, Environment Variable or Jenkins Proxy config from 'Jenkins->Manage Jenkins->Manage Plugins->Advanced Tab'.

We also tried with "-Dno.proxy=kubernetes.default.svc,kubernetes.default,..." parameter set with no luck.

Note that, we're able to access Kubernetes API pod console of the Jenkins server via 'curl' with appropriate proxy environment variables set.

Please find below exception message we got;

Failed to initialize Kubernetes secret provider
java.io.IOException: Failed to authenticate with proxy
at okhttp3.internal.connection.RealConnection.createTunnel(RealConnection.java:410)
at okhttp3.internal.connection.RealConnection.connectTunnel(RealConnection.java:220)
at okhttp3.internal.connection.RealConnection.connect(RealConnection.java:161)
at okhttp3.internal.connection.StreamAllocation.findConnection(StreamAllocation.java:258)
at okhttp3.internal.connection.StreamAllocation.findHealthyConnection(StreamAllocation.java:135)
at okhttp3.internal.connection.StreamAllocation.newStream(StreamAllocation.java:114)
at okhttp3.internal.connection.ConnectInterceptor.intercept(ConnectInterceptor.java:42)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.java:93)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.java:93)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.java:127)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at io.fabric8.kubernetes.client.utils.BackwardsCompatibilityInterceptor.intercept(BackwardsCompatibilityInterceptor.java:133)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at io.fabric8.kubernetes.client.utils.TokenRefreshInterceptor.intercept(TokenRefreshInterceptor.java:42)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at io.fabric8.kubernetes.client.utils.ImpersonatorInterceptor.intercept(ImpersonatorInterceptor.java:68)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at io.fabric8.kubernetes.client.utils.HttpClientUtils.lambda$createApplicableInterceptors$6(HttpClientUtils.java:284)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121)
at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:257)
at okhttp3.RealCall.execute(RealCall.java:93)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleResponse(OperationSupport.java:541)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleResponse(OperationSupport.java:504)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleResponse(OperationSupport.java:487)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.listRequestHelper(BaseOperation.java:163)
Caused: io.fabric8.kubernetes.client.KubernetesClientException: Operation: [list] for kind: [Secret] with name: [null] in namespace: [jenkins] failed.
at io.fabric8.kubernetes.client.KubernetesClientException.launderThrowable(KubernetesClientException.java:64)
at io.fabric8.kubernetes.client.KubernetesClientException.launderThrowable(KubernetesClientException.java:72)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.listRequestHelper(BaseOperation.java:170)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.list(BaseOperation.java:672)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.list(BaseOperation.java:86)
at com.cloudbees.jenkins.plugins.kubernetes_credentials_provider.KubernetesCredentialProvider.startWatchingForSecrets(KubernetesCredentialProvider.java:116)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at hudson.init.TaskMethodFinder.invoke(TaskMethodFinder.java:104)
at hudson.init.TaskMethodFinder$TaskImpl.run(TaskMethodFinder.java:175)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:296)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:1131)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:214)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117)
at jenkins.security.ImpersonatingExecutorService$1.run(ImpersonatingExecutorService.java:68)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)