maven : UnknownHostException: repo.maven.apache.org

Question

I am having this maven problem :

[ERROR] Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6: Could not transfer artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (http://repo.maven.apache.org/maven2): repo.maven.apache.org: Unknown host repo.maven.apache.org -> [Help 1] org.apache.maven.plugin.PluginResolutionException: Plugin org.apache.maven.plugins:maven-resources-plugin:2.6 or one of its dependencies could not be resolved: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6 at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:129) at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getPluginDescriptor(DefaultMavenPluginManager.java:142) at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getMojoDescriptor(DefaultMavenPluginManager.java:261) at org.apache.maven.plugin.DefaultBuildPluginManager.getMojoDescriptor(DefaultBuildPluginManager.java:185) at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecution(DefaultLifecycleExecutionPlanCalculator.java:152) at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.setupMojoExecutions(DefaultLifecycleExecutionPlanCalculator.java:139) at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.calculateExecutionPlan(DefaultLifecycleExecutionPlanCalculator.java:116) at org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator.calculateExecutionPlan(DefaultLifecycleExecutionPlanCalculator.java:129) at org.apache.maven.lifecycle.internal.BuilderCommon.resolveBuildPlan(BuilderCommon.java:92) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59) at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156) at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196) at org.apache.maven.cli.MavenCli.main(MavenCli.java:141) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:622) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352) Caused by: org.sonatype.aether.resolution.ArtifactDescriptorException: Failed to read artifact descriptor for org.apache.maven.plugins:maven-resources-plugin:jar:2.6 at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:296) at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.readArtifactDescriptor(DefaultArtifactDescriptorReader.java:186) at org.sonatype.aether.impl.internal.DefaultRepositorySystem.readArtifactDescriptor(DefaultRepositorySystem.java:279) at org.apache.maven.plugin.internal.DefaultPluginDependenciesResolver.resolve(DefaultPluginDependenciesResolver.java:115) ... 25 more Caused by: org.sonatype.aether.resolution.ArtifactResolutionException: Could not transfer artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (http://repo.maven.apache.org/maven2): repo.maven.apache.org at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:538) at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:216) at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:193) at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:281) ... 28 more Caused by: org.sonatype.aether.transfer.ArtifactTransferException: Could not transfer artifact org.apache.maven.plugins:maven-resources-plugin:pom:2.6 from/to central (http://repo.maven.apache.org/maven2): repo.maven.apache.org at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(WagonRepositoryConnector.java:951) at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(WagonRepositoryConnector.java:939) at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.run(WagonRepositoryConnector.java:669) at org.sonatype.aether.util.concurrency.RunnableErrorForwarder$1.run(RunnableErrorForwarder.java:60) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:701) Caused by: org.apache.maven.wagon.TransferFailedException: repo.maven.apache.org at org.apache.maven.wagon.shared.http.AbstractHttpClientWagon.fillInputData(AbstractHttpClientWagon.java:567) at org.apache.maven.wagon.StreamWagon.getInputStream(StreamWagon.java:116) at org.apache.maven.wagon.StreamWagon.getIfNewer(StreamWagon.java:88) at org.apache.maven.wagon.StreamWagon.get(StreamWagon.java:61) at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.run(WagonRepositoryConnector.java:601) ... 4 more Caused by: java.net.UnknownHostException: repo.maven.apache.org at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:175) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:385) at java.net.Socket.connect(Socket.java:546) at java.net.Socket.connect(Socket.java:495) at java.net.Socket.(Socket.java:392) at java.net.Socket.(Socket.java:266) at org.apache.commons.httpclient.protocol.DefaultProtocolSocketFactory.createSocket(DefaultProtocolSocketFactory.java:80) at org.apache.commons.httpclient.protocol.DefaultProtocolSocketFactory.createSocket(DefaultProtocolSocketFactory.java:122) at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707) at org.apache.commons.httpclient.MultiThreadedHttpConnectionManager$HttpConnectionAdapter.open(MultiThreadedHttpConnectionManager.java:1361) at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387) at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171) at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397) at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:323) at org.apache.maven.wagon.shared.http.AbstractHttpClientWagon.execute(AbstractHttpClientWagon.java:446) at org.apache.maven.wagon.shared.http.AbstractHttpClientWagon.fillInputData(AbstractHttpClientWagon.java:561) ... 8 more

I do have an internet connection. and I am not behind a proxy.

Solution

It was my Internet provider's fault: their DNS server could not resolve repo.maven.apache.org. I switched to a 3G Internet connection. It worked and the ping returns a response.

Comments

[Ewoks]

🤯 that's quite disturbing