Hi folks,   I've just installed a cluster with HDP 3.1 and I'm facing a problem setting PAM Authentication on Zeppelin.    After setting everything (from the documentation) I got the following error:   ============================= INFO [2019-10-11 12:26:48,848] ({qtp466505482-23} NotebookServer.java[onOpen]:150) - New connection from 10.22.9.120 : 33070 ERROR [2019-10-11 12:27:03,661] ({qtp466505482-64} LoginRestApi.java[proceedToLogin]:181) - Exception in login:   org.apache.shiro.authc.AuthenticationException: Authentication failed for PAM. at org.apache.zeppelin.realm.PamRealm.doGetAuthenticationInfo(PamRealm.java:74) at org.apache.shiro.realm.AuthenticatingRealm.getAuthenticationInfo(AuthenticatingRealm.java:568) at org.apache.shiro.authc.pam.ModularRealmAuthenticator.doSingleRealmAuthentication(ModularRealmAuthenticator.java:180) at org.apache.shiro.authc.pam.ModularRealmAuthenticator.doAuthenticate(ModularRealmAuthenticator.java:267) at org.apache.shiro.authc.AbstractAuthenticator.authenticate(AbstractAuthenticator.java:198) at org.apache.shiro.mgt.AuthenticatingSecurityManager.authenticate(AuthenticatingSecurityManager.java:106) at org.apache.shiro.mgt.DefaultSecurityManager.login(DefaultSecurityManager.java:270) at org.apache.shiro.subject.support.DelegatingSubject.login(DelegatingSubject.java:256) at org.apache.zeppelin.rest.LoginRestApi.proceedToLogin(LoginRestApi.java:149) at org.apache.zeppelin.rest.LoginRestApi.postLogin(LoginRestApi.java:208) 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 org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory.lambda$static$0(ResourceMethodInvocationHandlerFactory.java:76) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:148) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:191) at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:200) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:103) at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:493) at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:415) at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:104) at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:277) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:272) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:268) at org.glassfish.jersey.internal.Errors.process(Errors.java:316) at org.glassfish.jersey.internal.Errors.process(Errors.java:298) at org.glassfish.jersey.internal.Errors.process(Errors.java:268) at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:289) at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:256) at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:703) at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:416) at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:370) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:389) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:342) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:229) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:865) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1655) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at org.apache.zeppelin.server.CorsFilter.doFilter(CorsFilter.java:72) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1317) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1219) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:219) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) at org.eclipse.jetty.server.Server.handle(Server.java:531) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:352) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:281) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:102) at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:762) at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:680) at java.lang.Thread.run(Thread.java:745) Caused by: org.jvnet.libpam.PAMException: pam_authenticate failed : Authentication failure at org.jvnet.libpam.PAM.check(PAM.java:106) at org.jvnet.libpam.PAM.authenticate(PAM.java:124) at org.apache.zeppelin.realm.PamRealm.doGetAuthenticationInfo(PamRealm.java:72) ... 82 more   WARN [2019-10-11 12:27:03,672] ({qtp466505482-64} LoginRestApi.java[postLogin]:215) - {"status":"FORBIDDEN","message":"","body":""} =============================     The output of /var/log/auth.log also shows some strange messages, including "unexpected response from failed conversation function".   ============================= Oct 11 11:56:11 hypatia-0 java: pam_unix(sshd:auth): unexpected response from failed conversation function Oct 11 11:56:11 hypatia-0 su[32645]: Successful su for zeppelin by root Oct 11 11:56:11 hypatia-0 su[32645]: + ??? root:zeppelin Oct 11 11:56:11 hypatia-0 su[32645]: pam_unix(su:session): session opened for user zeppelin by (uid=0) Oct 11 11:56:11 hypatia-0 systemd-logind[861]: New session c1695 of user zeppelin. Oct 11 11:56:11 hypatia-0 unix_chkpwd[32634]: check pass; user unknown Oct 11 11:56:11 hypatia-0 unix_chkpwd[32634]: password check failed for user (angelo) Oct 11 11:56:11 hypatia-0 java: pam_unix(sshd:auth): authentication failure; logname= uid=1096 euid=1096 tty= ruser= rhost=   user=angelo Oct 11 11:56:11 hypatia-0 su[32645]: pam_unix(su:session): session closed for user zeppelin Oct 11 11:56:11 hypatia-0 systemd-logind[861]: Removed session c1695. =========================================     To debug this I wrote my own java code to authenticate to PAM using the code from Shimo tutorial (https://shiro.apache.org/tutorial.html), and that one worked. I believe therefore that something in the current Zeppelin version has screwed the interface to PAM.   Can you get a look on it and check if there is something to do?   Best regards ... View more