Error java.net.UnknownHostException while starting grails

Question

I am trying to work on grails through command prompt.

I am using the below versions:

| Grails Version: 3.2.3
| Groovy Version: 2.4.7
| JVM Version: 1.8.0_112

The following error is thrown (using --stacktrace option)

| Error Error occurred running Grails CLI: This is usually a temporary
error during hostname resolution and means that the local server did
not receive a response from an authoritative server (repo.grails.org)
(NOTE: Stack trace has been filtered. Use --verbose to see entire
trace.)

java.net.UnknownHostException: This is usually a temporary error
during hostname  resolution and means that the local server did not
receive a response from an a uthoritative server (repo.grails.org)
at org.apache.http.impl.conn.SystemDefaultDnsResolver.resolve(SystemDefa
ultDnsResolver.java:45)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.resolveHost
name(DefaultClientConnectionOperator.java:278)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnect
ion(DefaultClientConnectionOperator.java:162)
at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedCli
entConnectionImpl.java:294)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(Default
RequestDirector.java:643)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultReq
uestDirector.java:479)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpCl
ient.java:906)
at org.apache.http.impl.client.DecompressingHttpClient.execute(Decompres
singHttpClient.java:137)
at org.eclipse.aether.transport.http.HttpTransporter.execute(HttpTranspo
rter.java:287)
at org.eclipse.aether.transport.http.HttpTransporter.implGet(HttpTranspo
rter.java:243)
at org.eclipse.aether.spi.connector.transport.AbstractTransporter.get(Ab
stractTransporter.java:59)
at org.eclipse.aether.connector.basic.BasicRepositoryConnector$GetTaskRu
nner.runTask(BasicRepositoryConnector.java:447)
at org.eclipse.aether.connector.basic.BasicRepositoryConnector$TaskRunne
r.run(BasicRepositoryConnector.java:350)
at org.eclipse.aether.util.concurrency.RunnableErrorForwarder$1.run(Runn
ableErrorForwarder.java:67)
at org.eclipse.aether.connector.basic.BasicRepositoryConnector$DirectExe
cutor.execute(BasicRepositoryConnector.java:581)
at org.eclipse.aether.connector.basic.BasicRepositoryConnector.get(Basic
RepositoryConnector.java:249)
at org.eclipse.aether.internal.impl.DefaultArtifactResolver.performDownl
oads(DefaultArtifactResolver.java:520)
at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(Defa
ultArtifactResolver.java:421)
at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtif
acts(DefaultArtifactResolver.java:246)
at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtif
act(DefaultArtifactResolver.java:223)
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.
loadPom(DefaultArtifactDescriptorReader.java:320)
at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.
readArtifactDescriptor(DefaultArtifactDescriptorReader.java:217)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.resolveCa
chedArtifactDescriptor(DefaultDependencyCollector.java:535)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.getArtifa
ctDescriptorResult(DefaultDependencyCollector.java:519)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.processDe
pendency(DefaultDependencyCollector.java:409)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.processDe
pendency(DefaultDependencyCollector.java:363)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.process(D
efaultDependencyCollector.java:351)
at org.eclipse.aether.internal.impl.DefaultDependencyCollector.collectDe
pendencies(DefaultDependencyCollector.java:254)
at org.eclipse.aether.internal.impl.DefaultRepositorySystem.resolveDepen
dencies(DefaultRepositorySystem.java:341)
at org.springframework.boot.cli.compiler.grape.AetherGrapeEngine.resolve
(AetherGrapeEngine.java:302)
at org.springframework.boot.cli.compiler.grape.AetherGrapeEngine.resolve
(AetherGrapeEngine.java:284)
at org.springframework.boot.cli.compiler.grape.AetherGrapeEngine.resolve
(AetherGrapeEngine.java:276)
at org.grails.cli.boot.GrailsDependencyVersions.<init>(GrailsDependencyV
ersions.groovy:53)
at org.grails.cli.boot.GrailsDependencyVersions.<init>(GrailsDependencyV
ersions.groovy:49)
at org.grails.cli.profile.repository.MavenProfileRepository.<init>(Maven
ProfileRepository.groovy:53)
at org.grails.cli.GrailsCli.createMavenProfileRepository(GrailsCli.groov
y:333)
at org.grails.cli.GrailsCli.execute(GrailsCli.groovy:234)
at org.grails.cli.GrailsCli.main(GrailsCli.groovy:159)

| Error Error occurred running Grails CLI: This is usually a temporary
error dur ing hostname resolution and means that the local server did
not receive a respon se from an authoritative server (repo.grails.org)

Kindly help me resolve the above issue.

Answer 1

Most likely reason is your internet is not working or your are behind a proxy. See http://docs.grails.org/latest/guide/conf.html#proxyConfig for how to configure your proxy settings