AMQ214016: Failed to create netty connection

Issue

• The following exception can bee seen in the broker log file:

2018-10-07 01:54:42,387 Thread-87016 (ActiveMQ-client-global-threads) ERROR org.apache.activemq.artemis.core.client:792 - AMQ214016: Failed to create netty connection
java.net.UnknownHostException: hostname.example.org
    at java.net.InetAddress.getAllByName0(InetAddress.java:1280)
    at java.net.InetAddress.getAllByName(InetAddress.java:1192)
    at java.net.InetAddress.getAllByName(InetAddress.java:1126)
    at java.net.InetAddress.getByName(InetAddress.java:1076)
    at org.apache.activemq.artemis.shaded.io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:146)
    at org.apache.activemq.artemis.shaded.io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:143)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.activemq.artemis.shaded.io.netty.util.internal.SocketUtils.addressByName(SocketUtils.java:143)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.DefaultNameResolver.doResolve(DefaultNameResolver.java:43)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.SimpleNameResolver.resolve(SimpleNameResolver.java:63)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.SimpleNameResolver.resolve(SimpleNameResolver.java:55)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.InetSocketAddressResolver.doResolve(InetSocketAddressResolver.java:57)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.InetSocketAddressResolver.doResolve(InetSocketAddressResolver.java:32)
    at org.apache.activemq.artemis.shaded.io.netty.resolver.AbstractAddressResolver.resolve(AbstractAddressResolver.java:108)
    at org.apache.activemq.artemis.shaded.io.netty.bootstrap.Bootstrap.doResolveAndConnect0(Bootstrap.java:208)
    at org.apache.activemq.artemis.shaded.io.netty.bootstrap.Bootstrap.access$000(Bootstrap.java:49)
    at org.apache.activemq.artemis.shaded.io.netty.bootstrap.Bootstrap$1.operationComplete(Bootstrap.java:188)
    at org.apache.activemq.artemis.shaded.io.netty.bootstrap.Bootstrap$1.operationComplete(Bootstrap.java:174)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:507)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:481)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:420)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:104)
    at org.apache.activemq.artemis.shaded.io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:82)
    at org.apache.activemq.artemis.shaded.io.netty.channel.AbstractChannel$AbstractUnsafe.safeSetSuccess(AbstractChannel.java:978)
    at org.apache.activemq.artemis.shaded.io.netty.channel.AbstractChannel$AbstractUnsafe.register0(AbstractChannel.java:512)
    at org.apache.activemq.artemis.shaded.io.netty.channel.AbstractChannel$AbstractUnsafe.access$200(AbstractChannel.java:423)
    at org.apache.activemq.artemis.shaded.io.netty.channel.AbstractChannel$AbstractUnsafe$1.run(AbstractChannel.java:482)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:403)
    at org.apache.activemq.artemis.shaded.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:463)
    at org.apache.activemq.artemis.shaded.io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
    at java.lang.Thread.run(Thread.java:748)