Hello everyone,
I’ve tried to connect to a machine’s PLC with Ignition via OPC UA.
The PLC allows anonymous connection thus i do not have a user or password .
I already connected to the PLC using UA Expert without any problems.
When i try to connect via Ignition from the same server i get a FAULTED connection with this additional text:
java.lang.NullPointerException: Cannot invoke "String.hashCode()" because "<local1>" is null
at org.eclipse.milo.opcua.stack.core.transport.TransportProfile.fromUri(TransportProfile.java:26)
at org.eclipse.milo.opcua.stack.client.UaStackClient.create(UaStackClient.java:389)
at org.eclipse.milo.opcua.sdk.client.OpcUaClient.create(OpcUaClient.java:158)
at com.inductiveautomation.ignition.gateway.opcua.client.ManagedClientKt.createClient(ManagedClient.kt:220)
at com.inductiveautomation.ignition.gateway.opcua.client.ManagedClientKt.initialize(ManagedClient.kt:141)
at com.inductiveautomation.ignition.gateway.opcua.client.ManagedClientKt.access$initialize(ManagedClient.kt:1)
at com.inductiveautomation.ignition.gateway.opcua.client.ManagedClientKt$initialize$1.invokeSuspend(ManagedClient.kt)
at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)
8.1.36 (b2024010211)
Azul Systems, Inc. 17.0.8
In the Logs i have the following messages
2025-11-07 11:36:56:361 webserver-5106140
Error looking up endpoint
java.util.concurrent.ExecutionException: java.net.UnknownHostException: No such host is known (SIMATIC)
at java.base/java.util.concurrent.CompletableFuture.reportGet(Unknown Source)
at java.base/java.util.concurrent.CompletableFuture.get(Unknown Source)
at com.inductiveautomation.ignition.gateway.opcua.client.connection.web.discovery.wizardsteps.ChooseDiscoveryServerStep.getEndpoints(ChooseDiscoveryServerStep.java:116)
at com.inductiveautomation.ignition.gateway.opcua.client.connection.web.discovery.wizardsteps.ChooseDiscoveryServerStep.next(ChooseDiscoveryServerStep.java:103)
at org.apache.wicket.extensions.wizard.dynamic.DynamicWizardModel.next(DynamicWizardModel.java:126)
at com.inductiveautomation.ignition.gateway.opcua.client.connection.web.discovery.EndpointWizardButtonBar$NextButton.onClick(EndpointWizardButtonBar.java:26)
at org.apache.wicket.extensions.wizard.WizardButton.onSubmit(WizardButton.java:88)
at org.apache.wicket.markup.html.form.Form.delegateSubmit(Form.java:1304)
at org.apache.wicket.markup.html.form.Form.process(Form.java:967)
at org.apache.wicket.markup.html.form.Form.onFormSubmitted(Form.java:789)
at org.apache.wicket.markup.html.form.Form.onFormSubmitted(Form.java:701)
at jdk.internal.reflect.GeneratedMethodAccessor131.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.wicket.RequestListenerInterface.internalInvoke(RequestListenerInterface.java:258)
at org.apache.wicket.RequestListenerInterface.invoke(RequestListenerInterface.java:216)
at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.invokeListener(ListenerInterfaceRequestHandler.java:243)
at org.apache.wicket.core.request.handler.ListenerInterfaceRequestHandler.respond(ListenerInterfaceRequestHandler.java:236)
at org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:890)
at org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64)
at org.apache.wicket.request.cycle.RequestCycle.execute(RequestCycle.java:261)
at org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:218)
at org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:289)
at org.apache.wicket.protocol.http.WicketFilter.processRequestCycle(WicketFilter.java:259)
at org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:201)
at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:282)
at org.eclipse.jetty.servlet.FilterHolder.doFilter(FilterHolder.java:210)
at org.eclipse.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1635)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:527)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:131)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:578)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:223)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1570)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:221)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1384)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:176)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:484)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1543)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:174)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1306)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:129)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122)
at com.inductiveautomation.catapult.handlers.RemoteHostNameLookupHandler.handle(RemoteHostNameLookupHandler.java:121)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122)
at org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:301)
at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:51)
at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:141)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122)
at org.eclipse.jetty.server.Server.handle(Server.java:563)
at org.eclipse.jetty.server.HttpChannel.lambda$handle$0(HttpChannel.java:505)
at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:762)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:497)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:282)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:314)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:100)
at org.eclipse.jetty.io.ssl.SslConnection$DecryptedEndPoint.onFillable(SslConnection.java:558)
at org.eclipse.jetty.io.ssl.SslConnection.onFillable(SslConnection.java:379)
at org.eclipse.jetty.io.ssl.SslConnection$2.succeeded(SslConnection.java:146)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:100)
at org.eclipse.jetty.io.SelectableChannelEndPoint$1.run(SelectableChannelEndPoint.java:53)
at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.runTask(AdaptiveExecutionStrategy.java:416)
at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.consumeTask(AdaptiveExecutionStrategy.java:385)
at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.tryProduce(AdaptiveExecutionStrategy.java:272)
at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.lambda$new$0(AdaptiveExecutionStrategy.java:140)
at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:411)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:969)
at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.doRunJob(QueuedThreadPool.java:1194)
at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1149)
at java.base/java.lang.Thread.run(Unknown Source)
Caused by: java.net.UnknownHostException: No such host is known (SIMATIC)
at java.base/java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
at java.base/java.net.InetAddress$PlatformNameService.lookupAllHostAddr(Unknown Source)
at java.base/java.net.InetAddress.getAddressesFromNameService(Unknown Source)
at java.base/java.net.InetAddress$NameServiceAddresses.get(Unknown Source)
at java.base/java.net.InetAddress.getAllByName0(Unknown Source)
at java.base/java.net.InetAddress.getAllByName(Unknown Source)
at java.base/java.net.InetAddress.getAllByName(Unknown Source)
at java.base/java.net.InetAddress.getByName(Unknown Source)
at io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:156)
at io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:153)
at java.base/java.security.AccessController.doPrivileged(Unknown Source)
at io.netty.util.internal.SocketUtils.addressByName(SocketUtils.java:153)
at io.netty.resolver.DefaultNameResolver.doResolve(DefaultNameResolver.java:41)
at io.netty.resolver.SimpleNameResolver.resolve(SimpleNameResolver.java:61)
at io.netty.resolver.SimpleNameResolver.resolve(SimpleNameResolver.java:53)
at io.netty.resolver.InetSocketAddressResolver.doResolve(InetSocketAddressResolver.java:55)
at io.netty.resolver.InetSocketAddressResolver.doResolve(InetSocketAddressResolver.java:31)
at io.netty.resolver.AbstractAddressResolver.resolve(AbstractAddressResolver.java:106)
at io.netty.bootstrap.Bootstrap.doResolveAndConnect0(Bootstrap.java:220)
at io.netty.bootstrap.Bootstrap.access$000(Bootstrap.java:46)
at io.netty.bootstrap.Bootstrap$1.operationComplete(Bootstrap.java:189)
at io.netty.bootstrap.Bootstrap$1.operationComplete(Bootstrap.java:175)
at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:590)
at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:557)
at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:492)
at io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:636)
at io.netty.util.concurrent.DefaultPromise.setSuccess0(DefaultPromise.java:625)
at io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:105)
at io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:84)
at io.netty.channel.AbstractChannel$AbstractUnsafe.safeSetSuccess(AbstractChannel.java:990)
at io.netty.channel.AbstractChannel$AbstractUnsafe.register0(AbstractChannel.java:516)
at io.netty.channel.AbstractChannel$AbstractUnsafe.access$200(AbstractChannel.java:429)
at io.netty.channel.AbstractChannel$AbstractUnsafe$1.run(AbstractChannel.java:486)
at io.netty.util.concurrent.AbstractEventExecutor.runTask(AbstractEventExecutor.java:174)
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:167)
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:470)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:569)
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997)
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
... 1 common frames omitted
2025-11-07 11:37:02:191 webserver-5106141
Unable to reach host: SIMATIC at port: 4845
2025-11-07 11:37:34:429 webserver-5103958
Certificate has not been trusted. Connection to OPC server may not work properly.
I have already trusted the certificate and set a hostname override with the correct IP address.
I have also delete the certificate from the trust store and readded it and also deactivated the certificate validation in the connection properties.
Had someone already this problem and has a solution?
Ignition 8.1.36
Thanks for your help in advance and Best Regards,
Gerald
