Revert "Use HostName for message bus, but fix HostName to work with dev machines"

27 files changed, 225 insertions, 172 deletions

diff --git a/config-model/src/main/java/com/yahoo/config/model/provision/Hosts.java b/config-model/src/main/java/com/yahoo/config/model/provision/Hosts.java
index fbd5e712d3d..6a5abee7cb3 100644
--- a/config-model/src/main/java/com/yahoo/config/model/provision/Hosts.java
+++ b/config-model/src/main/java/com/yahoo/config/model/provision/Hosts.java
@@ -2,6 +2,7 @@
 package com.yahoo.config.model.provision;
 
 import com.google.common.collect.ImmutableMap;
+import com.yahoo.cloud.config.ConfigserverConfig;
 import com.yahoo.config.model.builder.xml.XmlHelper;
 import com.yahoo.net.HostName;
 import com.yahoo.text.XML;
@@ -75,7 +76,7 @@ public class Hosts {
                 throw new RuntimeException("Missing 'name' attribute for host.");
             }
             if ("localhost".equals(name)) {
-                name = HostName.getHostName();
+                name = HostName.getLocalhost();
             }
             final List<String> hostAliases = VespaDomBuilder.getHostAliases(hostE.getChildNodes());
             if (hostAliases.isEmpty()) {
diff --git a/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java b/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
index fb706e7201f..fe8b3935fcf 100644
--- a/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
+++ b/config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java
@@ -26,7 +26,7 @@ public class SingleNodeProvisioner implements HostProvisioner {
 
     public SingleNodeProvisioner() {
         try {
-            host = new Host(HostSystem.lookupCanonicalHostname(HostName.getHostName()));
+            host = new Host(HostSystem.lookupCanonicalHostname(HostName.getLocalhost()));
             this.hostSpec = new HostSpec(host.hostname(), host.aliases());
         }
         catch (UnknownHostException e) {
diff --git a/config-model/src/main/java/com/yahoo/vespa/model/container/configserver/ConfigserverCluster.java b/config-model/src/main/java/com/yahoo/vespa/model/container/configserver/ConfigserverCluster.java
index 96c80c57ab2..ef0f4882f1c 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/container/configserver/ConfigserverCluster.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/container/configserver/ConfigserverCluster.java
@@ -52,7 +52,7 @@ public class ConfigserverCluster extends AbstractConfigProducer
 
     @Override
     public void getConfig(ZookeeperServerConfig.Builder builder) {
-        String myhostname = HostName.getHostName();
+        String myhostname = HostName.getLocalhost();
         int myid = 0;
         int i = 0;
         for (ConfigServer server : getConfigServers()) {
@@ -115,7 +115,7 @@ public class ConfigserverCluster extends AbstractConfigProducer
             builder.defaultContentFlavor(options.defaultContentFlavor().get());
         }
 
-        builder.serverId(HostName.getHostName());
+        builder.serverId(HostName.getLocalhost());
         if (!containerCluster.getHttp().getHttpServer().getConnectorFactories().isEmpty()) {
             builder.httpport(containerCluster.getHttp().getHttpServer().getConnectorFactories().get(0).getListenPort());
         }
@@ -144,7 +144,7 @@ public class ConfigserverCluster extends AbstractConfigProducer
         if (options.allConfigServers().length > 0) {
             return options.allConfigServers();
         } else {
-            return new ConfigServer[]{new ConfigServer(HostName.getHostName(), Optional.<Integer>empty()) };
+            return new ConfigServer[]{new ConfigServer(HostName.getLocalhost(), Optional.<Integer>empty()) };
         }
     }
 
diff --git a/config-model/src/test/java/com/yahoo/config/model/deploy/SystemModelTestCase.java b/config-model/src/test/java/com/yahoo/config/model/deploy/SystemModelTestCase.java
index dc0ace32c1b..6be85fb19e4 100644
--- a/config-model/src/test/java/com/yahoo/config/model/deploy/SystemModelTestCase.java
+++ b/config-model/src/test/java/com/yahoo/config/model/deploy/SystemModelTestCase.java
@@ -78,7 +78,7 @@ public class SystemModelTestCase {
 
         // Verify configIds from vespaModel
         assertTrue(12 <= vespaModel.getConfigIds().size());
-        String localhost = HostName.getHostName();
+        String localhost = HostName.getLocalhost();
         String localhostConfigId = "hosts/" + localhost;
         Set<String> configIds = vespaModel.getConfigIds();
         assertTrue(configIds.contains("client"));
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/admin/AdminTestCase.java b/config-model/src/test/java/com/yahoo/vespa/model/admin/AdminTestCase.java
index f203fbce328..a8554c54867 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/admin/AdminTestCase.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/admin/AdminTestCase.java
@@ -8,6 +8,7 @@ import com.yahoo.cloud.config.SentinelConfig;
 import com.yahoo.config.model.ApplicationConfigProducerRoot;
 import com.yahoo.config.model.deploy.DeployProperties;
 import com.yahoo.config.model.deploy.DeployState;
+import com.yahoo.config.model.test.MockApplicationPackage;
 import com.yahoo.config.model.test.TestDriver;
 import com.yahoo.config.model.test.TestRoot;
 import com.yahoo.config.provision.ApplicationId;
@@ -23,7 +24,10 @@ import com.yahoo.vespa.model.container.component.Component;
 import com.yahoo.vespa.model.container.component.StatisticsComponent;
 import com.yahoo.vespa.model.test.utils.VespaModelCreatorWithFilePkg;
 import org.junit.Test;
+import org.xml.sax.SAXException;
 
+import java.io.IOException;
+import java.util.List;
 import java.util.Set;
 
 import static org.hamcrest.CoreMatchers.is;
@@ -61,7 +65,7 @@ public class AdminTestCase {
 
         // Verify configIds
         Set<String> configIds = vespaModel.getConfigIds();
-        String localhost = HostName.getHostName();
+        String localhost = HostName.getLocalhost();
         String localhostConfigId = "hosts/" + localhost;
         assertTrue(configIds.contains(localhostConfigId));
         assertTrue(configIds.contains("admin/logserver"));
@@ -115,7 +119,7 @@ public class AdminTestCase {
 
         // Verify configIds
         Set<String> configIds = vespaModel.getConfigIds();
-        String localhost = HostName.getHostName();
+        String localhost = HostName.getLocalhost();
         String localhostConfigId = "hosts/" + localhost;
         assertTrue(configIds.contains(localhostConfigId));
         assertTrue(configIds.contains("admin/logserver"));
@@ -152,7 +156,7 @@ public class AdminTestCase {
                         tenant("quux").
                         applicationName("foo").instanceName("bim").build()).build()).build();
         TestRoot root = new TestDriver().buildModel(state);
-        String localhost = HostName.getHostName();
+        String localhost = HostName.getLocalhost();
         SentinelConfig config = root.getConfig(SentinelConfig.class, "hosts/" + localhost);
         assertThat(config.application().tenant(), is("quux"));
         assertThat(config.application().name(), is("foo"));
@@ -175,7 +179,7 @@ public class AdminTestCase {
 
         // Verify configIds
         Set<String> configIds = vespaModel.getConfigIds();
-        String localhost = HostName.getHostName();
+        String localhost = HostName.getLocalhost();
         String localhostConfigId = "hosts/" + localhost;
         assertTrue(configIds.contains(localhostConfigId));
         assertTrue(configIds.contains("admin/logserver"));
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/clients/test/Gateway20TestCase.java b/config-model/src/test/java/com/yahoo/vespa/model/clients/test/Gateway20TestCase.java
index 579abf6d2c6..5987ab8410a 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/clients/test/Gateway20TestCase.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/clients/test/Gateway20TestCase.java
@@ -21,7 +21,7 @@ import static org.junit.Assert.*;
  * @author <a href="mailto:gunnarga@yahoo-inc.com">Gunnar Gauslaa Bergem</a>
  */
 public class Gateway20TestCase {
-    private static String hostname = HostName.getHostName();  // Using the same way of getting hostname as filedistribution model
+    private static String hostname = HostName.getLocalhost();  // Using the same way of getting hostname as filedistribution model
 
     @Test
     public void testSimpleDocprocV3() throws Exception {
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/container/configserver/ConfigserverClusterTest.java b/config-model/src/test/java/com/yahoo/vespa/model/container/configserver/ConfigserverClusterTest.java
index d9fc3cd9007..170586bef85 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/container/configserver/ConfigserverClusterTest.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/container/configserver/ConfigserverClusterTest.java
@@ -71,7 +71,7 @@ public class ConfigserverClusterTest {
         assertThat(config.configModelPluginDir().get(0), is(Defaults.getDefaults().vespaHome() + "lib/jars/config-models"));
         assertThat(config.rpcport(), is(12345));
         assertThat(config.httpport(), is(1337));
-        assertThat(config.serverId(), is(HostName.getHostName()));
+        assertThat(config.serverId(), is(HostName.getLocalhost()));
         assertTrue(config.useVespaVersionInRequest());
         assertThat(config.numParallelTenantLoaders(), is(4));
         assertFalse(config.multitenant());
diff --git a/config-model/src/test/java/com/yahoo/vespa/model/test/VespaModelTestCase.java b/config-model/src/test/java/com/yahoo/vespa/model/test/VespaModelTestCase.java
index 5bb01c87d0f..87fb5e567a5 100644
--- a/config-model/src/test/java/com/yahoo/vespa/model/test/VespaModelTestCase.java
+++ b/config-model/src/test/java/com/yahoo/vespa/model/test/VespaModelTestCase.java
@@ -23,6 +23,7 @@ import com.yahoo.container.core.ContainerHttpConfig;
 import com.yahoo.document.config.DocumentmanagerConfig;
 import com.yahoo.messagebus.MessagebusConfig;
 import com.yahoo.net.HostName;
+import com.yahoo.net.LinuxInetAddress;
 import com.yahoo.vespa.config.ConfigKey;
 import com.yahoo.vespa.config.ConfigPayload;
 import com.yahoo.vespa.config.ConfigPayloadBuilder;
@@ -101,7 +102,7 @@ public class VespaModelTestCase {
         LogdConfig.Builder b = new LogdConfig.Builder();
         b = (LogdConfig.Builder) model.getConfig(b, "");
         LogdConfig c = new LogdConfig(b);
-        assertEquals(HostSystem.lookupCanonicalHostname(HostName.getHostName()), c.logserver().host());
+        assertEquals(HostSystem.lookupCanonicalHostname(HostName.getLocalhost()), c.logserver().host());
 
         SlobroksConfig.Builder sb = new SlobroksConfig.Builder();
         sb = (com.yahoo.cloud.config.SlobroksConfig.Builder) model.getConfig(sb, "");
@@ -112,7 +113,7 @@ public class VespaModelTestCase {
         zb = (ZookeepersConfig.Builder) model.getConfig(zb, "");
         ZookeepersConfig zc = new ZookeepersConfig(zb);
         assertEquals(zc.zookeeperserverlist().split(",").length, 2);
-        assertTrue(zc.zookeeperserverlist().startsWith(HostSystem.lookupCanonicalHostname(HostName.getHostName())));
+        assertTrue(zc.zookeeperserverlist().startsWith(HostSystem.lookupCanonicalHostname(HostName.getLocalhost())));
 
         ApplicationIdConfig.Builder appIdBuilder = new ApplicationIdConfig.Builder();
         appIdBuilder = (ApplicationIdConfig.Builder) model.getConfig(appIdBuilder, "");
@@ -126,11 +127,11 @@ public class VespaModelTestCase {
     public void testHostsConfig() {
         VespaModel model = getVespaModel(TESTDIR + "app_qrserverandgw");
         LogdConfig config = getLogdConfig(model, "");
-        assertEquals(config.logserver().host(), HostName.getHostName());
+        assertEquals(config.logserver().host(), HostName.getLocalhost());
         assertNotNull(config);
         config = getLogdConfig(model, "hosts");
         assertNotNull(config);
-        assertEquals(config.logserver().host(), HostName.getHostName());
+        assertEquals(config.logserver().host(), HostName.getLocalhost());
     }
 
     private static LogdConfig getLogdConfig(VespaModel model, String configId) {
@@ -157,7 +158,7 @@ public class VespaModelTestCase {
         LogdConfig config = getLogdConfig(model, "");
         assertNotNull(config);
         assertEquals(config.logserver().host(), "foo");
-        config = getLogdConfig(model, "hosts/" + HostName.getHostName() + "/logd");
+        config = getLogdConfig(model, "hosts/" + HostName.getLocalhost() + "/logd");
         assertNotNull(config);
         assertEquals(config.logserver().host(), "foo");
     }
diff --git a/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java b/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java
index b1eb05fa76b..52df1cff117 100644
--- a/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java
+++ b/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java
@@ -424,7 +424,7 @@ public class ConfigUtils {
     }
 
     public static String getCanonicalHostName() {
-        return HostName.getHostName();
+        return HostName.getLocalhost();
     }
 
     /**
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDBRegistry.java b/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDBRegistry.java
index 307a0163331..37cea22e420 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDBRegistry.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDBRegistry.java
@@ -35,7 +35,7 @@ public class FileDBRegistry implements FileRegistry {
 
     @Override
     public String fileSourceHost() {
-        return HostName.getHostName();
+        return HostName.getLocalhost();
     }
 
     @Override
diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/rpc/GetConfigProcessor.java b/configserver/src/main/java/com/yahoo/vespa/config/server/rpc/GetConfigProcessor.java
index 6d9e1a9e6c1..310c7ceeef7 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/rpc/GetConfigProcessor.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/rpc/GetConfigProcessor.java
@@ -27,7 +27,7 @@ import java.util.logging.Logger;
 class GetConfigProcessor implements Runnable {
 
     private static final Logger log = Logger.getLogger(GetConfigProcessor.class.getName());
-    private static final String localHostName = HostName.getHostName();
+    private static final String localHostName = HostName.getLocalhost();
 
     private final JRTServerConfigRequest request;
     /* True only when this request has expired its server timeout and we need to respond to the client */
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/rpc/TestWithRpc.java b/configserver/src/test/java/com/yahoo/vespa/config/server/rpc/TestWithRpc.java
index 4348b587596..8f1754357b2 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/rpc/TestWithRpc.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/rpc/TestWithRpc.java
@@ -43,7 +43,7 @@ import static org.junit.Assert.assertTrue;
 public class TestWithRpc {
 
     private final ManualClock clock = new ManualClock(Instant.ofEpochMilli(100));
-    private final String myHostname = HostName.getHostName();
+    private final String myHostname = HostName.getLocalhost();
     private final HostLivenessTracker hostLivenessTracker = new ConfigRequestHostLivenessTracker(clock);
 
     protected RpcServer rpcServer;
diff --git a/container-core/src/main/java/com/yahoo/container/osgi/ContainerRpcAdaptor.java b/container-core/src/main/java/com/yahoo/container/osgi/ContainerRpcAdaptor.java
index 3906e3a57ff..8b0ed41cd8c 100644
--- a/container-core/src/main/java/com/yahoo/container/osgi/ContainerRpcAdaptor.java
+++ b/container-core/src/main/java/com/yahoo/container/osgi/ContainerRpcAdaptor.java
@@ -43,7 +43,7 @@ public class ContainerRpcAdaptor extends AbstractRpcAdaptor {
     public ContainerRpcAdaptor(Osgi osgi) {
         this.osgi = osgi;
         this.supervisor = new Supervisor(new Transport());
-        this.hostname = HostName.getHostName();
+        this.hostname = HostName.getLocalhost();
 
         bindCommands(supervisor);
     }
diff --git a/container-search/src/main/java/com/yahoo/prelude/cluster/ClusterSearcher.java b/container-search/src/main/java/com/yahoo/prelude/cluster/ClusterSearcher.java
index c7829dfde7f..36ae057b418 100644
--- a/container-search/src/main/java/com/yahoo/prelude/cluster/ClusterSearcher.java
+++ b/container-search/src/main/java/com/yahoo/prelude/cluster/ClusterSearcher.java
@@ -192,7 +192,7 @@ public class ClusterSearcher extends Searcher {
         if (InetAddress.getByName(host).isLoopbackAddress())
             return false;
         else
-            return !host.equals(HostName.getHostName());
+            return !host.equals(HostName.getLocalhost());
     }
 
     private static ClusterParams makeClusterParams(int searchclusterIndex,
diff --git a/container-search/src/main/java/com/yahoo/prelude/fastsearch/FastSearcher.java b/container-search/src/main/java/com/yahoo/prelude/fastsearch/FastSearcher.java
index ee059edb519..504c5dd363a 100644
--- a/container-search/src/main/java/com/yahoo/prelude/fastsearch/FastSearcher.java
+++ b/container-search/src/main/java/com/yahoo/prelude/fastsearch/FastSearcher.java
@@ -94,7 +94,7 @@ public class FastSearcher extends VespaBackEndSearcher {
         this.dispatchBackend = dispatchBackend;
         this.fs4ResourcePool = fs4ResourcePool;
         this.dispatcher = dispatcher;
-        this.selfHostname = HostName.getHostName();
+        this.selfHostname = HostName.getLocalhost();
     }
 
     private static SimpleDateFormat isoDateFormat;
diff --git a/container-search/src/main/java/com/yahoo/search/dispatch/SearchCluster.java b/container-search/src/main/java/com/yahoo/search/dispatch/SearchCluster.java
index c1a07759718..b6ee70802d8 100644
--- a/container-search/src/main/java/com/yahoo/search/dispatch/SearchCluster.java
+++ b/container-search/src/main/java/com/yahoo/search/dispatch/SearchCluster.java
@@ -91,7 +91,7 @@ public class SearchCluster implements NodeManager<SearchCluster.Node> {
             nodesByHostBuilder.put(node.hostname(), node);
         this.nodesByHost = nodesByHostBuilder.build();
 
-        this.directDispatchTarget = findDirectDispatchTarget(HostName.getHostName(), size, containerClusterSize,
+        this.directDispatchTarget = findDirectDispatchTarget(HostName.getLocalhost(), size, containerClusterSize,
                                                              nodesByHost, groups);
 
         // Set up monitoring of the fs4 interface of the nodes
diff --git a/container-search/src/test/java/com/yahoo/fs4/mplex/BackendTestCase.java b/container-search/src/test/java/com/yahoo/fs4/mplex/BackendTestCase.java
index f9c14a81d13..52a66fa6db9 100644
--- a/container-search/src/test/java/com/yahoo/fs4/mplex/BackendTestCase.java
+++ b/container-search/src/test/java/com/yahoo/fs4/mplex/BackendTestCase.java
@@ -1,18 +1,9 @@
 // Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.fs4.mplex;
 
-import com.yahoo.container.search.Fs4Config;
-import com.yahoo.fs4.BasicPacket;
-import com.yahoo.fs4.ChannelTimeoutException;
-import com.yahoo.fs4.PacketListener;
-import com.yahoo.fs4.PingPacket;
-import com.yahoo.fs4.QueryPacket;
-import com.yahoo.fs4.mplex.Backend.BackendStatistics;
-import com.yahoo.prelude.fastsearch.FS4ResourcePool;
-import com.yahoo.search.Query;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import java.io.IOException;
 import java.net.InetAddress;
@@ -22,9 +13,21 @@ import java.net.Socket;
 import java.nio.ByteBuffer;
 import java.util.logging.Logger;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import com.yahoo.container.search.Fs4Config;
+import com.yahoo.net.HostName;
+import com.yahoo.net.LinuxInetAddress;
+import com.yahoo.prelude.fastsearch.FS4ResourcePool;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.yahoo.fs4.BasicPacket;
+import com.yahoo.fs4.ChannelTimeoutException;
+import com.yahoo.fs4.PacketListener;
+import com.yahoo.fs4.PingPacket;
+import com.yahoo.fs4.QueryPacket;
+import com.yahoo.fs4.mplex.Backend.BackendStatistics;
+import com.yahoo.search.Query;
 
 /**
  * Test networking code for talking to dispatch.
@@ -111,6 +114,7 @@ public class BackendTestCase {
 
         public MockServer() throws IOException {
             ServerSocket socket = new ServerSocket(0, 50, InetAddress.getLoopbackAddress());
+            //ServerSocket socket = new ServerSocket(0, 50, LinuxInetAddress.getLocalHost());
             host = (InetSocketAddress) socket.getLocalSocketAddress();
             dispatch = new MockDispatch(socket);
             worker = new Thread(dispatch);
diff --git a/container-search/src/test/java/com/yahoo/prelude/fastsearch/test/FastSearcherTester.java b/container-search/src/test/java/com/yahoo/prelude/fastsearch/test/FastSearcherTester.java
index 93b18da215a..d2638be4bc7 100644
--- a/container-search/src/test/java/com/yahoo/prelude/fastsearch/test/FastSearcherTester.java
+++ b/container-search/src/test/java/com/yahoo/prelude/fastsearch/test/FastSearcherTester.java
@@ -27,7 +27,7 @@ import static org.junit.Assert.assertEquals;
  */
 class FastSearcherTester {
 
-    public static final String selfHostname = HostName.getHostName();
+    public static final String selfHostname = HostName.getLocalhost();
 
     private final MockFS4ResourcePool mockFS4ResourcePool;
     private final FastSearcher fastSearcher;
diff --git a/docker-api/src/main/java/com/yahoo/vespa/hosted/dockerapi/DockerImpl.java b/docker-api/src/main/java/com/yahoo/vespa/hosted/dockerapi/DockerImpl.java
index c0ffe367259..5e5185bc6be 100644
--- a/docker-api/src/main/java/com/yahoo/vespa/hosted/dockerapi/DockerImpl.java
+++ b/docker-api/src/main/java/com/yahoo/vespa/hosted/dockerapi/DockerImpl.java
@@ -124,7 +124,7 @@ public class DockerImpl implements Docker {
         if (! dockerClient.listNetworksCmd().withNameFilter(DOCKER_CUSTOM_MACVLAN_NETWORK_NAME).exec().isEmpty()) return;
 
         // Use IPv6 address if there is a mix of IP4 and IPv6 by taking the longest address.
-        List<InetAddress> hostAddresses = Arrays.asList(InetAddress.getAllByName(com.yahoo.net.HostName.getHostName()));
+        List<InetAddress> hostAddresses = Arrays.asList(InetAddress.getAllByName(com.yahoo.net.HostName.getLocalhost()));
         InetAddress hostAddress = Collections.max(hostAddresses,
                 (o1, o2) -> o1.getAddress().length - o2.getAddress().length);
 
@@ -563,7 +563,7 @@ public class DockerImpl implements Docker {
 
     private void setMetrics(MetricReceiverWrapper metricReceiver) {
         Dimensions dimensions = new Dimensions.Builder()
-                .add("host", HostName.getHostName())
+                .add("host", HostName.getLocalhost())
                 .add("role", "docker").build();
 
         numberOfRunningContainersGauge = metricReceiver.declareGauge(dimensions, "containers.running");
diff --git a/messagebus/src/main/java/com/yahoo/messagebus/network/Identity.java b/messagebus/src/main/java/com/yahoo/messagebus/network/Identity.java
index a10cd4b8a63..45887b072ab 100644
--- a/messagebus/src/main/java/com/yahoo/messagebus/network/Identity.java
+++ b/messagebus/src/main/java/com/yahoo/messagebus/network/Identity.java
@@ -1,7 +1,12 @@
 // Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.messagebus.network;
 
+import com.yahoo.log.LogLevel;
 import com.yahoo.net.HostName;
+import com.yahoo.net.LinuxInetAddress;
+
+import java.net.Inet6Address;
+import java.net.InetAddress;
 
 /**
  * This class encapsulates the identity of the application that uses this instance of message bus. This identity
@@ -23,7 +28,11 @@ public class Identity {
      * @param configId The config identifier for the application.
      */
     public Identity(String configId) {
-        hostname = HostName.getHostName(); // ... but fallback to hostname if we get an IPv6 address
+        InetAddress addr = LinuxInetAddress.getLocalHost(); // try hard to get a resolvable address
+        if (addr instanceof Inet6Address) // 
+            hostname = HostName.getLocalhost(); // ... but fallback to hostname if we get an IPv6 address
+        else
+            hostname = addr.getCanonicalHostName();
         servicePrefix = configId;
     }
 
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminImpl.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminImpl.java
index b86a3c11f70..15a33dddd3c 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminImpl.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/nodeadmin/NodeAdminImpl.java
@@ -75,7 +75,7 @@ public class NodeAdminImpl implements NodeAdmin {
         this.nodeAgentScanIntervalMillis = nodeAgentScanIntervalMillis;
 
         Dimensions dimensions = new Dimensions.Builder()
-                .add("host", HostName.getHostName())
+                .add("host", HostName.getLocalhost())
                 .add("role", "docker").build();
 
         this.numberOfContainersInActiveState = metricReceiver.declareGauge(dimensions, "nodes.state.active");
diff --git a/standalone-container/src/main/scala/com/yahoo/container/standalone/LocalFileDb.scala b/standalone-container/src/main/scala/com/yahoo/container/standalone/LocalFileDb.scala
index b1c7e9457ac..7af08a4685d 100644
--- a/standalone-container/src/main/scala/com/yahoo/container/standalone/LocalFileDb.scala
+++ b/standalone-container/src/main/scala/com/yahoo/container/standalone/LocalFileDb.scala
@@ -49,7 +49,7 @@ class LocalFileDb(appPath: Path) extends FileAcquirer with FileRegistry {
   }
 
   def fileSourceHost: String =
-    HostName.getHostName
+    HostName.getLocalhost
 
   def allRelativePaths: java.util.Set[String] = {
     new java.util.HashSet(fileReferenceToFile.values.map(_.getPath))
diff --git a/vespaclient-container-plugin/src/main/java/com/yahoo/vespa/http/server/FeedHandler.java b/vespaclient-container-plugin/src/main/java/com/yahoo/vespa/http/server/FeedHandler.java
index 78b33abedda..c37cb51d7ca 100644
--- a/vespaclient-container-plugin/src/main/java/com/yahoo/vespa/http/server/FeedHandler.java
+++ b/vespaclient-container-plugin/src/main/java/com/yahoo/vespa/http/server/FeedHandler.java
@@ -270,7 +270,7 @@ public class FeedHandler extends LoggingRequestHandler {
     }
 
     private static String resolveLocalHostname() {
-        String hostname = HostName.getHostName();
+        String hostname = HostName.getLocalhost();
         if (hostname.equals("localhost")) {
             return "";
         }
diff --git a/vespajlib/src/main/java/com/yahoo/net/HostName.java b/vespajlib/src/main/java/com/yahoo/net/HostName.java
index 061b53216c0..4e791ca117a 100644
--- a/vespajlib/src/main/java/com/yahoo/net/HostName.java
+++ b/vespajlib/src/main/java/com/yahoo/net/HostName.java
@@ -2,139 +2,40 @@
 package com.yahoo.net;
 
 import java.io.BufferedReader;
-import java.io.IOException;
 import java.io.InputStreamReader;
-import java.net.InetAddress;
-import java.net.NetworkInterface;
-import java.net.SocketException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-import java.util.Objects;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-import java.util.stream.Collectors;
 
 /**
- * Utilities for getting the hostname of the system running the JVM.
+ * Utilities for getting the hostname on a system running with the JVM. This is moved here from the old
+ * HostSystem#getHostName in config-model.
  *
  * @author lulf
- * @author bratseth
- * @author hakon
  */
 public class HostName {
 
-    private static final Logger logger = Logger.getLogger(HostName.class.getName());
-
-    private static String cachedHostName = null;
+    private static String myHost = null;
 
     /**
-     * Return a fully qualified hostname that resolves to an IP address on a network interface.
-     * Normally this is the same as the 'hostname' command, but on dev machines on WiFi,
-     * that IP isn't configured so we prefer a WiFi network interface IP address which is both reachable and
-     * has a DNS entry.
+     * Static method that returns the name of localhost using shell command "hostname".
+     * If you need a guaranteed resolvable name see LinuxINetAddress.
      *
-     * @return the preferred name of localhost
-     * @throws RuntimeException if accessing the network or the 'hostname' command fails
+     * @return the name of localhost.
+     * @throws RuntimeException if executing the command 'hostname' fails.
      */
-    public static synchronized String getHostName() {
-        if (cachedHostName == null) {
+    public static synchronized String getLocalhost() {
+        if (myHost == null) {
             try {
-                cachedHostName = getPreferredAddress().canonicalHostName;
-            } catch (Exception e) {
-                throw new RuntimeException("Failed to find a preferred hostname", e);
-            }
-        }
-        return cachedHostName;
-    }
-
-    private static Address getPreferredAddress() throws Exception {
-        List<Address> addresses = getReachableNetworkInterfaceAddresses();
-
-        // Prefer address matching the system hostname
-        String systemHostName = getSystemHostName();
-        List<Address> systemAddresses = addresses.stream()
-                .filter(address -> Objects.equals(address.canonicalHostName, systemHostName))
-                .collect(Collectors.toList());
-        if (systemAddresses.size() >= 1) {
-            return systemAddresses.iterator().next();
-        }
-
-        // Otherwise, prefer non-local address.
-        List<Address> nonLocalAddresses = addresses.stream()
-                .filter(address -> !address.ipAddress.isAnyLocalAddress())
-                .collect(Collectors.toList());
-        if (nonLocalAddresses.size() >= 1) {
-            return nonLocalAddresses.iterator().next();
-        }
-
-        // Otherwise, pick a local address.
-        List<Address> localAddresses = addresses.stream()
-                .filter(address -> address.ipAddress.isAnyLocalAddress())
-                .collect(Collectors.toList());
-        if (localAddresses.size() >= 1) {
-            return localAddresses.iterator().next();
-        }
-
-        throw new RuntimeException("Failed to find any addresses on the network interfaces that resolves to a DNS name");
-    }
-
-    // public for testing purposes (all testing machines should have a hostname
-    public static String getSystemHostName() throws Exception {
-        Process process = Runtime.getRuntime().exec("hostname");
-        BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
-        String hostname = in.readLine();
-        process.waitFor();
-        if (process.exitValue() != 0) {
-            throw new RuntimeException("Command 'hostname' failed with exit code " + process.exitValue());
-        }
-
-        return hostname;
-    }
-
-    private static class Address {
-
-        public final InetAddress ipAddress;
-        public final String canonicalHostName;
-
-        public Address(InetAddress ipAddress, String canonicalHostName) {
-            this.ipAddress = ipAddress;
-            this.canonicalHostName = canonicalHostName;
-        }
-
-    }
-
-    private static List<Address> getReachableNetworkInterfaceAddresses() throws SocketException {
-        List<Address> addresses = new ArrayList<>();
-
-        for (NetworkInterface networkInterface : Collections.list(NetworkInterface.getNetworkInterfaces())) {
-            for (InetAddress ipAddress : Collections.list(networkInterface.getInetAddresses())) {
-                String hostname = ipAddress.getCanonicalHostName();
-                if (Objects.equals(hostname, ipAddress.getHostAddress())) {
-                    // getCanonicalHostName() failed to get the fully qualified domain name
-                    continue;
-                }
-
-                try {
-                    // ping says ~50ms on my Fedora Lenovo, but that seems a lot for pinging oneself  - hakon
-                    int timeoutMs = 100;
-                    if ( ! ipAddress.isReachable(timeoutMs)) {
-                        // The network interface may be down, ignore address
-                        logger.log(Level.INFO, ipAddress.toString() + 
-                                               " is unreachable w/" + timeoutMs + "ms timeout, ignoring address");
-                        continue;
-                    }
-                } catch (IOException e) {
-                    // Why would this be different from !isReachable ?
-                    logger.log(Level.INFO, "Failed testing reachability of " + ipAddress + ", ignoring address", e);
-                    continue;
+                Process p = Runtime.getRuntime().exec("hostname");
+                BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));
+                myHost = in.readLine();
+                p.waitFor();
+                if (p.exitValue() != 0) {
+                    throw new RuntimeException("Command 'hostname' failed: exit("+p.exitValue()+")");
                 }
-
-                addresses.add(new Address(ipAddress, hostname));
+            } catch (Exception e) {
+                throw new RuntimeException("Failed when executing command 'hostname'", e);
             }
         }
-
-        return addresses;
+        return myHost;
     }
 
 }
diff --git a/vespajlib/src/main/java/com/yahoo/net/LinuxInetAddress.java b/vespajlib/src/main/java/com/yahoo/net/LinuxInetAddress.java
new file mode 100644
index 00000000000..9d50c99d77c
--- /dev/null
+++ b/vespajlib/src/main/java/com/yahoo/net/LinuxInetAddress.java
@@ -0,0 +1,98 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.net;
+
+import java.net.*;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.List;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+/**
+ * Utilities for returning localhost addresses on Linux.
+ * See http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4665037 on why this is necessary.
+ *
+ * @author bratseth
+ */
+public class LinuxInetAddress {
+
+    /**
+     * Returns an InetAddress representing a resolvable localhost address.
+     * A non-loopback address is preferred if available.
+     * An address that resolves to a hostname is preferred among non-loopback addresses.
+     * IPv4 is preferred over IPv6 among resolving addresses.
+     *
+     * @return a localhost address
+     */
+    // Note: Checking resolvability of ipV6 addresses takes a long time on some systems (over 5 seconds 
+    // for some addresses on my mac). This method is written to minimize the number of resolution checks done
+    // and to defer ip6 checks until necessary.
+    public static InetAddress getLocalHost() {
+        InetAddress fallback = InetAddress.getLoopbackAddress();
+        try {
+            fallback = InetAddress.getLocalHost();
+            List<InetAddress> nonLoopback =
+                getAllLocalFromNetwork().stream().filter(a -> ! a.isLoopbackAddress()).collect(Collectors.toList());
+            if (nonLoopback.isEmpty()) return fallback;
+            
+            // Invariant: We got all addresses without exception
+
+            List<InetAddress> ipV4 = nonLoopback.stream().filter(a -> a instanceof Inet4Address).collect(Collectors.toList());
+            for (InetAddress address : ipV4)
+                if (doesResolve(address))
+                    return address;
+
+            // Invariant: There are no resolving ip4 addresses
+            
+            List<InetAddress> ipV6 = nonLoopback.stream().filter(a -> a instanceof Inet4Address).collect(Collectors.toList());
+            for (InetAddress address : ipV6)
+                if (doesResolve(address))
+                    return address;
+
+            // Invariant: There are no resolving ip6 addresses either
+
+            if (! ipV4.isEmpty()) return ipV4.get(0);
+            return ipV6.get(0);
+        } catch (UnknownHostException e) {
+            return fallback;
+        }
+    }
+
+    /**
+     * Returns all local addresses of this host.
+     *
+     * @return an array of the addresses of this
+     * @throws UnknownHostException if we cannot access the network
+     */
+    public static InetAddress[] getAllLocal() throws UnknownHostException {
+        InetAddress[] localInetAddresses = InetAddress.getAllByName("127.0.0.1");
+        if ( ! localInetAddresses[0].isLoopbackAddress()) return localInetAddresses;
+        return getAllLocalFromNetwork().toArray(new InetAddress[0]);
+    }
+
+    /**
+     * Returns all local addresses of this host.
+     *
+     * @return a list of the addresses of this
+     * @throws UnknownHostException if we cannot access the network
+     */
+    private static List<InetAddress> getAllLocalFromNetwork() throws UnknownHostException {
+        try {
+            List<InetAddress> addresses = new ArrayList<>();
+            for (NetworkInterface networkInterface : Collections.list(NetworkInterface.getNetworkInterfaces()))
+                addresses.addAll(Collections.list(networkInterface.getInetAddresses()));
+            return addresses;
+        }
+        catch (SocketException ex) {
+            throw new UnknownHostException("127.0.0.1");
+        }
+    }
+
+    private static boolean doesResolve(InetAddress address) {
+        // The latter returns a name if resolvable to one and the host address otherwise
+        return ! address.getHostAddress().equals(address.getCanonicalHostName());
+    }
+
+}
diff --git a/vespajlib/src/test/java/com/yahoo/net/HostNameTestCase.java b/vespajlib/src/test/java/com/yahoo/net/HostNameTestCase.java
index 0534b02db60..98be9f0ef6f 100644
--- a/vespajlib/src/test/java/com/yahoo/net/HostNameTestCase.java
+++ b/vespajlib/src/test/java/com/yahoo/net/HostNameTestCase.java
@@ -9,15 +9,8 @@ import static org.junit.Assert.assertFalse;
  * @author lulf
  */
 public class HostNameTestCase {
-
     @Test
     public void testHostnameIsFound() {
-        assertFalse(HostName.getHostName().isEmpty());
+        assertFalse(HostName.getLocalhost().isEmpty());
     }
-
-    @Test
-    public void testSystemHostnameIsFound() throws Exception {
-        assertFalse(HostName.getSystemHostName().isEmpty());
-    }
-
 }
diff --git a/vespajlib/src/test/java/com/yahoo/net/LinuxInetAddressTestCase.java b/vespajlib/src/test/java/com/yahoo/net/LinuxInetAddressTestCase.java
new file mode 100755
index 00000000000..27b85a0864c
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/net/LinuxInetAddressTestCase.java
@@ -0,0 +1,42 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.

+package com.yahoo.net;

+

+import java.net.UnknownHostException;

+import java.net.InetAddress;

+import java.net.Inet4Address;

+

+/**

+ * @author Simon Thoresen

+ */

+public class LinuxInetAddressTestCase extends junit.framework.TestCase {

+

+    @SuppressWarnings("deprecation")

+    public void testPreferIPv4() throws UnknownHostException {

+        try {

+            // This test only works if there is at least one inet address returned.

+            InetAddress[] arr = LinuxInetAddress.getAllLocal();

+            if (arr.length > 0) {

+                // System.out.println("Got " + arr.length + " addresses.");

+

+                // And it can only make sure it is preferred if there is at least one ip v4 address.

+                boolean ipv4 = false;

+                for (int i = 0; i < arr.length; ++i) {

+                    // System.out.println("Address " + i + " is an instance of " + arr[i].getClass() + ".");

+                    if (arr[i] instanceof Inet4Address) {

+                        ipv4 = true;

+                    }

+                }

+

+                // And the only thing we test is that an ip v4 address is preferred.

+                if (ipv4) {

+                    InetAddress addr = LinuxInetAddress.getLocalHost();

+                    assertNotNull("IPv4 is prefered", addr instanceof Inet4Address);

+                }

+            }

+        }

+        catch (java.net.UnknownHostException e) {

+            // We're on vpn or have no network

+        }

+    }

+

+}