SunCertPathBuilderException: unable to find valid certification path to requested target when trying to use the old remoting-connector in JBoss EAP 7.1

Issue

• We enabled the old remoting-connector in JBoss EAP 7.1 and are using the jboss-ejb-client.xml server to server EJB configuration, but our client server is getting this exception when it tries to invoke the remote EJB, even though the client's remote-outbound-connection has SSL_ENABLED set to false.

The client server has:

            <outbound-connections>
                <remote-outbound-connection name="remote-ejb-connection" outbound-socket-binding-ref="remote-socket-ejb" security-realm="ejb-security-realm" username="ejbuser" protocol="remote">
                    <properties>
                        <property name="SASL_POLICY_NOANONYMOUS" value="false"/>
                        <property name="SSL_ENABLED" value="false"/>
                    </properties>
                </remote-outbound-connection>
            </outbound-connections>

The server side has:

        <subsystem xmlns="urn:jboss:domain:remoting:4.0">
            <endpoint/>
            <connector name="remoting-connector" socket-binding="remoting" security-realm="ApplicationRealm">
            </connector>
            <http-connector name="http-remoting-connector" connector-ref="default" security-realm="ApplicationRealm"/>
        </subsystem>

Caused by: javax.faces.el.EvaluationException: javax.ejb.NoSuchEJBException: EJBCLIENT000079: Unable to discover destination for request for EJB StatelessEJBLocator for "/ejb-client/Hello", view is interface com.jboss.examples.ejb.Hello, affinity is None
    at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:101)
    at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
    at javax.faces.component.UICommand.broadcast(UICommand.java:315)
    at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:790)
    at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1282)
    at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:658)
    ... 39 more
Caused by: javax.ejb.NoSuchEJBException: EJBCLIENT000079: Unable to discover destination for request for EJB StatelessEJBLocator for "/ejb-client/Hello", view is interface com.jboss.examples.ejb.Hello, affinity is None
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:592)
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:528)
    at org.jboss.ejb.protocol.remote.RemotingEJBClientInterceptor.handleInvocationResult(RemotingEJBClientInterceptor.java:56)
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:594)
...
    Suppressed: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
        at sun.security.ssl.Handshaker.checkThrown(Handshaker.java:1529)
        at sun.security.ssl.SSLEngineImpl.checkTaskThrown(SSLEngineImpl.java:535)
        at sun.security.ssl.SSLEngineImpl.writeAppRecord(SSLEngineImpl.java:1214)
        at sun.security.ssl.SSLEngineImpl.wrap(SSLEngineImpl.java:1186)
        at org.xnio.ssl.JsseSslConduitEngine.engineWrap(JsseSslConduitEngine.java:336)
...
    Caused by: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
        at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
        at sun.security.ssl.SSLEngineImpl.fatal(SSLEngineImpl.java:1728)
        at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:330)
        at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:322)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1614)
        at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:216)
        at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1052)
        at sun.security.ssl.Handshaker$1.run(Handshaker.java:992)
        at sun.security.ssl.Handshaker$1.run(Handshaker.java:989)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.security.ssl.Handshaker$DelegatedTask.run(Handshaker.java:1467)
        at org.xnio.ssl.JsseSslConduitEngine.handleHandshake(JsseSslConduitEngine.java:543)
...
    Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:397)
        at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)
        at sun.security.validator.Validator.validate(Validator.java:262)
        at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)
        at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:281)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:136)
        at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1601)
        ... 17 more
    Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
        at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
        at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:392)
        ... 23 more
    Suppressed: javax.ejb.NoSuchEJBException: WFLYEJB0056: Could not find EJB in matching deployment: StatelessEJBLocator for "/ejb-client/Hello", view is interface com.jboss.examples.ejb.Hello, affinity is None
        at org.jboss.as.ejb3.remote.LocalEjbReceiver.findBean(LocalEjbReceiver.java:401)
        at org.jboss.as.ejb3.remote.LocalEjbReceiver.processInvocation(LocalEjbReceiver.java:96)
        at org.jboss.ejb.client.EJBClientInvocationContext.sendRequest(EJBClientInvocationContext.java:479)
...
    Suppressed: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
        at sun.security.ssl.Handshaker.checkThrown(Handshaker.java:1529)
        at sun.security.ssl.SSLEngineImpl.checkTaskThrown(SSLEngineImpl.java:535)
        at sun.security.ssl.SSLEngineImpl.readNetRecord(SSLEngineImpl.java:813)
        at sun.security.ssl.SSLEngineImpl.unwrap(SSLEngineImpl.java:781)
        at javax.net.ssl.SSLEngine.unwrap(SSLEngine.java:624)
        at org.xnio.ssl.JsseSslConduitEngine.engineUnwrap(JsseSslConduitEngine.java:688)
        at org.xnio.ssl.JsseSslConduitEngine.unwrap(JsseSslConduitEngine.java:620)
...
    Caused by: javax.net.ssl.SSLHandshakeException: General SSLEngine problem
        at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
...
    Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:397)
        at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)
...
    Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
        at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
        at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
        at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
        at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:392)
        ... 25 more