UnknownHostException: druid-hadoop-demo in openstack instance

I am trying to do hadoop ingestion in openstack instance with docker but I get the following error when I try to start druid services:

Exception in thread “main” java.lang.RuntimeException: com.google.inject.CreationException: Unable to create injector, see the following errors:

  1. An exception was caught and reported. Message: java.net.UnknownHostException: druid-hadoop-demo

at com.google.inject.util.Modules$OverrideModule.configure(Modules.java:198)

1 error

at org.apache.druid.cli.GuiceRunnable.makeInjector(GuiceRunnable.java:71)

  at org.apache.druid.cli.ServerRunnable.run(ServerRunnable.java:56)

 at org.apache.druid.cli.Main.main(Main.java:118)

Caused by: com.google.inject.CreationException: Unable to create injector, see the following errors:

  1. An exception was caught and reported. Message: java.net.UnknownHostException: druid-hadoop-demo

at com.google.inject.util.Modules$OverrideModule.configure(Modules.java:198)

1 error

at com.google.inject.internal.Errors.throwCreationExceptionIfErrorsExist(Errors.java:470)

  at com.google.inject.internal.InternalInjectorCreator.initializeStatically(InternalInjectorCreator.java:155)

at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:107)

at com.google.inject.Guice.createInjector(Guice.java:99)

   at com.google.inject.Guice.createInjector(Guice.java:73)

   at com.google.inject.Guice.createInjector(Guice.java:62)

   at org.apache.druid.initialization.Initialization.makeInjectorWithModules(Initialization.java:419)

 at org.apache.druid.cli.GuiceRunnable.makeInjector(GuiceRunnable.java:68)

  ... 2 more

Caused by: java.lang.IllegalArgumentException: java.net.UnknownHostException: druid-hadoop-demo

  at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:417)

at org.apache.hadoop.hdfs.NameNodeProxiesClient.createProxyWithClientProtocol(NameNodeProxiesClient.java:132)

at org.apache.hadoop.hdfs.DFSClient.(DFSClient.java:359)

at org.apache.hadoop.hdfs.DFSClient.(DFSClient.java:293)

at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:157)

 at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2812)

  at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:100)

 at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2849)

 at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2831)

 at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:389)

at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:181)

at org.apache.druid.storage.hdfs.HdfsStorageDruidModule.configure(HdfsStorageDruidModule.java:105)

 at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:340)

at com.google.inject.spi.Elements.getElements(Elements.java:110)

   at com.google.inject.util.Modules$OverrideModule.configure(Modules.java:198)

at com.google.inject.AbstractModule.configure(AbstractModule.java:62)

at com.google.inject.spi.Elements$RecordingBinder.install(Elements.java:340)

at com.google.inject.spi.Elements.getElements(Elements.java:110)

   at com.google.inject.internal.InjectorShell$Builder.build(InjectorShell.java:138)

  at com.google.inject.internal.InternalInjectorCreator.build(InternalInjectorCreator.java:104)

… 7 more

Caused by: java.net.UnknownHostException: druid-hadoop-demo

… 27 more

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