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Posted to commits@ambari.apache.org by al...@apache.org on 2015/04/24 01:16:37 UTC

[3/3] ambari git commit: AMBARI-10679. Full Delete of Host : Switch config related tables to use host_id instead of host_name column (alejandro)

AMBARI-10679. Full Delete of Host : Switch config related tables to use host_id instead of host_name column (alejandro)


Project: http://git-wip-us.apache.org/repos/asf/ambari/repo
Commit: http://git-wip-us.apache.org/repos/asf/ambari/commit/290276c6
Tree: http://git-wip-us.apache.org/repos/asf/ambari/tree/290276c6
Diff: http://git-wip-us.apache.org/repos/asf/ambari/diff/290276c6

Branch: refs/heads/trunk
Commit: 290276c62152f331e0859c1d81534cc160471327
Parents: 9096775
Author: Alejandro Fernandez <af...@hortonworks.com>
Authored: Wed Apr 22 19:06:43 2015 -0700
Committer: Alejandro Fernandez <af...@hortonworks.com>
Committed: Thu Apr 23 16:16:30 2015 -0700

----------------------------------------------------------------------
 .../ServiceConfigVersionResponse.java           |  17 +-
 .../internal/ConfigGroupResourceProvider.java   |  35 ++-
 .../internal/UpgradeResourceProvider.java       |  25 ++-
 .../orm/cache/ConfigGroupHostMapping.java       |   4 +-
 .../orm/cache/ConfigGroupHostMappingImpl.java   |  43 ++--
 .../server/orm/cache/HostConfigMapping.java     |   8 +-
 .../server/orm/cache/HostConfigMappingImpl.java |  54 ++---
 .../orm/dao/ConfigGroupHostMappingDAO.java      |  46 ++--
 .../server/orm/dao/HostConfigMappingDAO.java    | 193 +++++++++--------
 .../apache/ambari/server/orm/dao/HostDAO.java   |  11 +
 .../entities/ConfigGroupHostMappingEntity.java  |  24 ++-
 .../ConfigGroupHostMappingEntityPK.java         |  16 +-
 .../orm/entities/HostConfigMappingEntity.java   |  18 +-
 .../orm/entities/HostConfigMappingEntityPK.java |  20 +-
 .../orm/entities/ServiceConfigEntity.java       |  12 +-
 .../org/apache/ambari/server/state/Cluster.java |   6 +-
 .../apache/ambari/server/state/Clusters.java    |  17 ++
 .../server/state/cluster/ClusterImpl.java       |  77 ++++---
 .../server/state/cluster/ClustersImpl.java      |  54 ++++-
 .../server/state/configgroup/ConfigGroup.java   |   6 +-
 .../state/configgroup/ConfigGroupFactory.java   |   2 +-
 .../state/configgroup/ConfigGroupImpl.java      |  38 ++--
 .../ambari/server/state/host/HostImpl.java      |  31 ++-
 .../server/upgrade/UpgradeCatalog210.java       |  51 ++++-
 .../main/resources/Ambari-DDL-MySQL-CREATE.sql  |  27 +--
 .../main/resources/Ambari-DDL-Oracle-CREATE.sql |  25 +--
 .../resources/Ambari-DDL-Postgres-CREATE.sql    |  25 +--
 .../Ambari-DDL-Postgres-EMBEDDED-CREATE.sql     |  25 +--
 .../resources/Ambari-DDL-SQLServer-CREATE.sql   |  21 +-
 .../AmbariManagementControllerTest.java         |  10 +-
 .../ConfigGroupResourceProviderTest.java        |  98 +++++++--
 .../server/orm/dao/ConfigGroupDAOTest.java      |  22 +-
 .../orm/dao/HostConfigMappingDAOTest.java       |  87 ++++----
 .../ambari/server/state/ConfigGroupTest.java    |   9 +-
 .../ambari/server/state/ConfigHelperTest.java   |   6 +-
 .../ambari/server/state/UpgradeHelperTest.java  |   5 +-
 .../server/state/cluster/ClusterTest.java       |  97 ++++++---
 .../svccomphost/ServiceComponentHostTest.java   | 214 ++++++++++---------
 .../ambari/server/upgrade/UpgradeTest.java      |  13 +-
 39 files changed, 867 insertions(+), 625 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/controller/ServiceConfigVersionResponse.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/controller/ServiceConfigVersionResponse.java b/ambari-server/src/main/java/org/apache/ambari/server/controller/ServiceConfigVersionResponse.java
index 9a07a29..c02bb6e 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/controller/ServiceConfigVersionResponse.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/controller/ServiceConfigVersionResponse.java
@@ -21,6 +21,9 @@ package org.apache.ambari.server.controller;
 
 import java.util.List;
 
+import com.google.inject.Inject;
+import org.apache.ambari.server.StaticallyInject;
+import org.apache.ambari.server.orm.dao.HostDAO;
 import org.apache.ambari.server.orm.entities.ClusterEntity;
 import org.apache.ambari.server.orm.entities.ServiceConfigEntity;
 import org.apache.ambari.server.orm.entities.StackEntity;
@@ -28,6 +31,7 @@ import org.apache.ambari.server.state.StackId;
 import org.codehaus.jackson.annotate.JsonProperty;
 import org.codehaus.jackson.map.annotate.JsonSerialize;
 
+@StaticallyInject
 public class ServiceConfigVersionResponse {
   @JsonProperty("cluster_name")
   @JsonSerialize(include = JsonSerialize.Inclusion.NON_NULL)
@@ -72,15 +76,14 @@ public class ServiceConfigVersionResponse {
   @JsonProperty("hosts")
   private final List<String> hosts;
 
+  @Inject
+  private static HostDAO hostDAO;
+
   /**
    * Constructor.
    *
-   * @param clusterName
-   * @param serviceName
-   * @param version
-   * @param isCurrent
-   * @param isCompatibleWithCurrentStack
-   * @param configurations
+   * @param serviceConfigEntity
+   * @param configGroupName
    */
   public ServiceConfigVersionResponse(ServiceConfigEntity serviceConfigEntity,
       String configGroupName) {
@@ -95,7 +98,7 @@ public class ServiceConfigVersionResponse {
     note = serviceConfigEntity.getNote();
     groupId = (null != serviceConfigEntity.getGroupId() ? serviceConfigEntity.getGroupId(): -1L);
     groupName = configGroupName;
-    hosts = serviceConfigEntity.getHostNames();
+    hosts = hostDAO.getHostNamesByHostIds(serviceConfigEntity.getHostIds());
 
     StackEntity serviceConfigStackEntity = serviceConfigEntity.getStack();
     StackEntity clusterStackEntity = clusterEntity.getClusterStateEntity().getCurrentStack();

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/ConfigGroupResourceProvider.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/ConfigGroupResourceProvider.java b/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/ConfigGroupResourceProvider.java
index 3fcb84b..68bad38 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/ConfigGroupResourceProvider.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/ConfigGroupResourceProvider.java
@@ -17,12 +17,14 @@
  */
 package org.apache.ambari.server.controller.internal;
 
+import com.google.inject.Inject;
 import org.apache.ambari.server.AmbariException;
 import org.apache.ambari.server.ClusterNotFoundException;
 import org.apache.ambari.server.ConfigGroupNotFoundException;
 import org.apache.ambari.server.DuplicateResourceException;
 import org.apache.ambari.server.HostNotFoundException;
 import org.apache.ambari.server.ParentObjectNotFoundException;
+import org.apache.ambari.server.StaticallyInject;
 import org.apache.ambari.server.controller.AmbariManagementController;
 import org.apache.ambari.server.controller.ConfigGroupRequest;
 import org.apache.ambari.server.controller.ConfigGroupResponse;
@@ -37,6 +39,8 @@ import org.apache.ambari.server.controller.spi.ResourcePredicateEvaluator;
 import org.apache.ambari.server.controller.spi.SystemException;
 import org.apache.ambari.server.controller.spi.UnsupportedPropertyException;
 import org.apache.ambari.server.controller.utilities.PropertyHelper;
+import org.apache.ambari.server.orm.dao.HostDAO;
+import org.apache.ambari.server.orm.entities.HostEntity;
 import org.apache.ambari.server.state.Cluster;
 import org.apache.ambari.server.state.Clusters;
 import org.apache.ambari.server.state.Config;
@@ -48,13 +52,16 @@ import org.apache.commons.lang.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+@StaticallyInject
 public class ConfigGroupResourceProvider extends
   AbstractControllerResourceProvider implements ResourcePredicateEvaluator {
 
@@ -86,6 +93,9 @@ public class ConfigGroupResourceProvider extends
   private static Set<String> pkPropertyIds = new HashSet<String>(Arrays
     .asList(new String[] { CONFIGGROUP_ID_PROPERTY_ID }));
 
+  @Inject
+  private static HostDAO hostDAO;
+
   /**
    * Create a  new resource provider for the given management controller.
    *
@@ -343,10 +353,11 @@ public class ConfigGroupResourceProvider extends
             // Has tag
             if (configGroup.getTag().equals(request.getTag())) {
               // Has a match with hosts
-              Set<String> groupHosts = new HashSet<String>(configGroup
-                .getHosts().keySet());
-              groupHosts.retainAll(request.getHosts());
-              if (!groupHosts.isEmpty()) {
+              List<Long> groupHostIds = new ArrayList<Long>(configGroup.getHosts().keySet());
+              Set<String> groupHostNames = new HashSet<String>(hostDAO.getHostNamesByHostIds(groupHostIds));
+
+              groupHostNames.retainAll(request.getHosts());
+              if (!groupHostNames.isEmpty()) {
                 responses.add(configGroup.convertToResponse());
               }
             }
@@ -362,7 +373,7 @@ public class ConfigGroupResourceProvider extends
     return responses;
   }
 
-  private void verifyHostList(Cluster cluster, Map<String, Host> hosts,
+  private void verifyHostList(Cluster cluster, Map<Long, Host> hosts,
                               ConfigGroupRequest request) throws AmbariException {
 
     Map<Long, ConfigGroup> configGroupMap = cluster.getConfigGroups();
@@ -472,14 +483,15 @@ public class ConfigGroupResourceProvider extends
       }
 
       // Find hosts
-      Map<String, Host> hosts = new HashMap<String, Host>();
+      Map<Long, Host> hosts = new HashMap<Long, Host>();
       if (request.getHosts() != null && !request.getHosts().isEmpty()) {
         for (String hostname : request.getHosts()) {
           Host host = clusters.getHost(hostname);
-          if (host == null) {
+          HostEntity hostEntity = hostDAO.findByName(hostname);
+          if (host == null || hostEntity == null) {
             throw new HostNotFoundException(hostname);
           }
-          hosts.put(hostname, host);
+          hosts.put(hostEntity.getHostId(), host);
         }
       }
 
@@ -568,14 +580,15 @@ public class ConfigGroupResourceProvider extends
       }
 
       // Update hosts
-      Map<String, Host> hosts = new HashMap<String, Host>();
+      Map<Long, Host> hosts = new HashMap<Long, Host>();
       if (request.getHosts() != null && !request.getHosts().isEmpty()) {
         for (String hostname : request.getHosts()) {
           Host host = clusters.getHost(hostname);
-          if (host == null) {
+          HostEntity hostEntity = hostDAO.findByName(hostname);
+          if (host == null || hostEntity == null) {
             throw new HostNotFoundException(hostname);
           }
-          hosts.put(hostname, host);
+          hosts.put(hostEntity.getHostId(), host);
         }
       }
 

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UpgradeResourceProvider.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UpgradeResourceProvider.java b/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UpgradeResourceProvider.java
index 730fba5..7de7348 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UpgradeResourceProvider.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/controller/internal/UpgradeResourceProvider.java
@@ -23,6 +23,7 @@ import static org.apache.ambari.server.agent.ExecutionCommand.KeyNames.VERSION;
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -59,11 +60,13 @@ import org.apache.ambari.server.controller.spi.Resource;
 import org.apache.ambari.server.controller.spi.ResourceAlreadyExistsException;
 import org.apache.ambari.server.controller.spi.SystemException;
 import org.apache.ambari.server.controller.spi.UnsupportedPropertyException;
+import org.apache.ambari.server.orm.dao.HostDAO;
 import org.apache.ambari.server.orm.dao.HostRoleCommandDAO;
 import org.apache.ambari.server.orm.dao.HostRoleCommandStatusSummaryDTO;
 import org.apache.ambari.server.orm.dao.RepositoryVersionDAO;
 import org.apache.ambari.server.orm.dao.RequestDAO;
 import org.apache.ambari.server.orm.dao.UpgradeDAO;
+import org.apache.ambari.server.orm.entities.HostEntity;
 import org.apache.ambari.server.orm.entities.RepositoryVersionEntity;
 import org.apache.ambari.server.orm.entities.RequestEntity;
 import org.apache.ambari.server.orm.entities.StackEntity;
@@ -170,6 +173,10 @@ public class UpgradeResourceProvider extends AbstractControllerResourceProvider
   @Inject
   private static HostRoleCommandDAO s_hostRoleCommandDAO = null;
 
+  @Inject
+  private static HostDAO s_hostDAO = null;
+
+
   /**
    * Used to generated the correct tasks and stages during an upgrade.
    */
@@ -901,6 +908,19 @@ public class UpgradeResourceProvider extends AbstractControllerResourceProvider
     String itemDetail = entity.getText();
     String stageText = StringUtils.abbreviate(entity.getText(), 255);
 
+    String hostName = null;
+    Collection<Long> hostIds = cluster.getAllHostsDesiredConfigs().keySet();
+    if (!hostIds.isEmpty()) {
+      Long hostId = hostIds.iterator().next();
+      HostEntity hostEntity = s_hostDAO.findById(hostId);
+      if (hostEntity != null) {
+        hostName = hostEntity.getHostName();
+      }
+    }
+    if (StringUtils.isBlank(hostName)) {
+      throw new AmbariException("Could not retrieve an arbitrary host name to use for the server-side command.");
+    }
+
     switch (task.getType()) {
       case MANUAL: {
         ManualTask mt = (ManualTask) task;
@@ -980,15 +1000,12 @@ public class UpgradeResourceProvider extends AbstractControllerResourceProvider
     stage.setStageId(stageId);
     entity.setStageId(Long.valueOf(stageId));
 
-    // !!! hack hack hack
-    String host = cluster.getAllHostsDesiredConfigs().keySet().iterator().next();
-
     stage.addServerActionCommand(task.getImplementationClass(),
         getManagementController().getAuthName(),
         Role.AMBARI_SERVER_ACTION,
         RoleCommand.EXECUTE,
         cluster.getClusterName(),
-        host,
+        hostName,
         new ServiceComponentHostServerActionEvent(StageUtils.getHostName(), System.currentTimeMillis()),
         commandParams,
         itemDetail,

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMapping.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMapping.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMapping.java
index 5c26a6c..ae3f076 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMapping.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMapping.java
@@ -24,12 +24,12 @@ import org.apache.ambari.server.state.configgroup.ConfigGroup;
 public interface ConfigGroupHostMapping {
   
   public Long getConfigGroupId();
-  public String getHostname();
+  public Long getHostId();
   public Host getHost();
   public ConfigGroup getConfigGroup();
   
   public void setConfigGroupId(Long configGroupId);
-  public void setHostname(String hostname);
+  public void setHostId(Long setHostId);
   public void setHost(Host host);
   public void setConfigGroup(ConfigGroup configGroup);
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMappingImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMappingImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMappingImpl.java
index 54e1ca0..741b02e 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMappingImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/ConfigGroupHostMappingImpl.java
@@ -24,7 +24,7 @@ import org.apache.ambari.server.state.configgroup.ConfigGroup;
 public class ConfigGroupHostMappingImpl implements ConfigGroupHostMapping {
 
   private Long configGroupId;
-  private String hostname;
+  private Long hostId;
   private Host host;
   private ConfigGroup configGroup;
 
@@ -34,8 +34,8 @@ public class ConfigGroupHostMappingImpl implements ConfigGroupHostMapping {
   }
 
   @Override
-  public String getHostname() {
-    return hostname;
+  public Long getHostId() {
+    return hostId;
   }
 
   @Override
@@ -51,25 +51,21 @@ public class ConfigGroupHostMappingImpl implements ConfigGroupHostMapping {
   @Override
   public void setConfigGroupId(Long configGroupId) {
     this.configGroupId = configGroupId;
-
   }
 
   @Override
-  public void setHostname(String hostname) {
-    this.hostname = hostname;
-
+  public void setHostId(Long hostId) {
+    this.hostId = hostId;
   }
 
   @Override
   public void setHost(Host host) {
     this.host = host;
-
   }
 
   @Override
   public void setConfigGroup(ConfigGroup configGroup) {
     this.configGroup = configGroup;
-
   }
 
   @Override
@@ -82,7 +78,7 @@ public class ConfigGroupHostMappingImpl implements ConfigGroupHostMapping {
         prime * result
             + ((configGroupId == null) ? 0 : configGroupId.hashCode());
     result = prime * result + ((host == null) ? 0 : host.hashCode());
-    result = prime * result + ((hostname == null) ? 0 : hostname.hashCode());
+    result = prime * result + ((hostId == null) ? 0 : hostId.hashCode());
     return result;
   }
 
@@ -95,27 +91,12 @@ public class ConfigGroupHostMappingImpl implements ConfigGroupHostMapping {
     if (getClass() != obj.getClass())
       return false;
     ConfigGroupHostMappingImpl other = (ConfigGroupHostMappingImpl) obj;
-    if (configGroup == null) {
-      if (other.configGroup != null)
-        return false;
-    } else if (!configGroup.equals(other.configGroup))
-      return false;
-    if (configGroupId == null) {
-      if (other.configGroupId != null)
-        return false;
-    } else if (!configGroupId.equals(other.configGroupId))
-      return false;
-    if (host == null) {
-      if (other.host != null)
-        return false;
-    } else if (!host.equals(other.host))
-      return false;
-    if (hostname == null) {
-      if (other.hostname != null)
-        return false;
-    } else if (!hostname.equals(other.hostname))
-      return false;
+
+    if (configGroup != null ? !configGroup.equals(other.configGroup) : other.configGroup != null) return false;
+    if (configGroupId != null ? !configGroupId.equals(other.configGroupId) : other.configGroupId != null) return false;
+    if (host != null ? !host.equals(other.host) : other.host != null) return false;
+    if (hostId != null ? !hostId.equals(other.hostId) : other.hostId != null) return false;
+    
     return true;
   }
-
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMapping.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMapping.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMapping.java
index 269daa9..d5afc15 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMapping.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMapping.java
@@ -21,9 +21,9 @@ public interface HostConfigMapping {
   
   public Long getClusterId();
   public void setClusterId(Long clusterId);
-  
-  public String getHostName();
-  public void setHostName(String hostName);
+
+  public Long getHostId();
+  public void setHostId(Long hostId);
   
   public String getType();
   public void setType(String type);
@@ -42,6 +42,4 @@ public interface HostConfigMapping {
   
   public Integer getSelected();
   public void setSelected(Integer selected);
-  
-
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMappingImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMappingImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMappingImpl.java
index 407aeb6..ab86c9b 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMappingImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/cache/HostConfigMappingImpl.java
@@ -22,7 +22,7 @@ package org.apache.ambari.server.orm.cache;
 public class HostConfigMappingImpl implements HostConfigMapping {
   
   private Long clusterId;
-  private String hostName;
+  private Long hostId;
   private String type;
   private Long createTimestamp;
   private String version;
@@ -34,7 +34,7 @@ public class HostConfigMappingImpl implements HostConfigMapping {
   
   public HostConfigMappingImpl(HostConfigMapping entry) {
     setClusterId(entry.getClusterId());
-    setHostName(entry.getHostName());
+    setHostId(entry.getHostId());
     setType(entry.getType());
     setCreateTimestamp(entry.getCreateTimestamp());
     setVersion(entry.getVersion());
@@ -57,17 +57,17 @@ public class HostConfigMappingImpl implements HostConfigMapping {
       throw new RuntimeException("ClusterId couldn't be null");
     this.clusterId = clusterId;
   }
-  
+
   @Override
-  public String getHostName() {
-    return hostName;
+  public Long getHostId() {
+    return hostId;
   }
-  
+
   @Override
-  public void setHostName(String hostName) {
-    if (hostName == null)
-      throw new RuntimeException("HostName couldn't be null");
-    this.hostName = hostName;
+  public void setHostId(Long hostId) {
+    if (hostId == null)
+      throw new RuntimeException("HostId couldn't be null");
+    this.hostId = hostId;
   }
   
   @Override
@@ -143,10 +143,8 @@ public class HostConfigMappingImpl implements HostConfigMapping {
     final int prime = 31;
     int result = 1;
     result = prime * result + ((clusterId == null) ? 0 : clusterId.hashCode());
-    result =
-        prime * result
-            + ((createTimestamp == null) ? 0 : createTimestamp.hashCode());
-    result = prime * result + ((hostName == null) ? 0 : hostName.hashCode());
+    result = prime * result + ((createTimestamp == null) ? 0 : createTimestamp.hashCode());
+    result = prime * result + ((hostId == null) ? 0 : hostId.hashCode());
     result = prime * result + ((type == null) ? 0 : type.hashCode());
     return result;
   }
@@ -159,29 +157,13 @@ public class HostConfigMappingImpl implements HostConfigMapping {
       return false;
     if (getClass() != obj.getClass())
       return false;
+
     HostConfigMappingImpl other = (HostConfigMappingImpl) obj;
-    if (clusterId == null) {
-      if (other.clusterId != null)
-        return false;
-    } else if (!clusterId.equals(other.clusterId))
-      return false;
-    if (createTimestamp == null) {
-      if (other.createTimestamp != null)
-        return false;
-    } else if (!createTimestamp.equals(other.createTimestamp))
-      return false;
-    if (hostName == null) {
-      if (other.hostName != null)
-        return false;
-    } else if (!hostName.equals(other.hostName))
-      return false;
-    if (type == null) {
-      if (other.type != null)
-        return false;
-    } else if (!type.equals(other.type))
-      return false;
+    if (clusterId != null ? !clusterId.equals(other.clusterId) : other.clusterId != null) return false;
+    if (createTimestamp != null ? !createTimestamp.equals(other.createTimestamp) : other.createTimestamp != null) return false;
+    if (hostId != null ? !hostId.equals(other.hostId) : other.hostId != null) return false;
+    if (type != null ? !type.equals(other.type) : other.type != null) return false;
+
     return true;
   }
-  
-
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/ConfigGroupHostMappingDAO.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/ConfigGroupHostMappingDAO.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/ConfigGroupHostMappingDAO.java
index 592679e..4628a4c 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/ConfigGroupHostMappingDAO.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/ConfigGroupHostMappingDAO.java
@@ -64,7 +64,7 @@ public class ConfigGroupHostMappingDAO {
   
   private final ReadWriteLock gl = new ReentrantReadWriteLock();
   
-  private Map<String, Set<ConfigGroupHostMapping>> configGroupHostMappingByHost;
+  private Map<Long, Set<ConfigGroupHostMapping>> configGroupHostMappingByHost;
   
   private volatile boolean cacheLoaded;
 
@@ -75,7 +75,7 @@ public class ConfigGroupHostMappingDAO {
       gl.writeLock().lock();
       try {
         if (configGroupHostMappingByHost == null) {
-          configGroupHostMappingByHost = new WeakHashMap<String, Set<ConfigGroupHostMapping>>();
+          configGroupHostMappingByHost = new WeakHashMap<Long, Set<ConfigGroupHostMapping>>();
           
           TypedQuery<ConfigGroupHostMappingEntity> query = entityManagerProvider.get().createQuery(
               "SELECT entity FROM ConfigGroupHostMappingEntity entity",
@@ -85,11 +85,11 @@ public class ConfigGroupHostMappingDAO {
           
           for (ConfigGroupHostMappingEntity configGroupHostMappingEntity : configGroupHostMappingEntities) {
 
-            Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get((configGroupHostMappingEntity.getHostname()));
+            Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get((configGroupHostMappingEntity.getHostId()));
               
             if (setByHost == null) {
               setByHost = new HashSet<ConfigGroupHostMapping>();
-              configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostname(), setByHost);
+              configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostId(), setByHost);
             }
        
             ConfigGroupHostMapping configGroupHostMapping = buildConfigGroupHostMapping(configGroupHostMappingEntity);
@@ -121,14 +121,14 @@ public class ConfigGroupHostMappingDAO {
   }
 
   @RequiresSession
-  public Set<ConfigGroupHostMapping> findByHost(String hostname) {
+  public Set<ConfigGroupHostMapping> findByHostId(Long hostId) {
     
     populateCache();
     
-    if (!configGroupHostMappingByHost.containsKey(hostname))
+    if (!configGroupHostMappingByHost.containsKey(hostId))
       return null;
     
-    Set<ConfigGroupHostMapping> set = new HashSet<ConfigGroupHostMapping>(configGroupHostMappingByHost.get(hostname));
+    Set<ConfigGroupHostMapping> set = new HashSet<ConfigGroupHostMapping>(configGroupHostMappingByHost.get(hostId));
     
     return set;
     
@@ -169,33 +169,29 @@ public class ConfigGroupHostMappingDAO {
   @Transactional
   public void create(ConfigGroupHostMappingEntity
                          configGroupHostMappingEntity) {
-    
     populateCache();
 
     entityManagerProvider.get().persist(configGroupHostMappingEntity);
     
     //create in cache
-    Set<ConfigGroupHostMapping> set = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostname());
+    Set<ConfigGroupHostMapping> set = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostId());
     if (set == null){
       set = new HashSet<ConfigGroupHostMapping>();
-      configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostname(), set);
+      configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostId(), set);
     }
     
     set.add(buildConfigGroupHostMapping(configGroupHostMappingEntity));
-    
   }
 
-
-
   @Transactional
   public ConfigGroupHostMappingEntity merge(ConfigGroupHostMappingEntity configGroupHostMappingEntity) {
     
     populateCache();
     
-    Set<ConfigGroupHostMapping> set = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostname());
+    Set<ConfigGroupHostMapping> set = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostId());
     if (set == null){
       set = new HashSet<ConfigGroupHostMapping>();
-      configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostname(), set);
+      configGroupHostMappingByHost.put(configGroupHostMappingEntity.getHostId(), set);
     }
     
     //Update object in set
@@ -223,7 +219,7 @@ public class ConfigGroupHostMappingDAO {
     
     entityManagerProvider.get().remove(merge(configGroupHostMappingEntity));
     
-    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostname());
+    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get(configGroupHostMappingEntity.getHostId());
     
     if (setByHost != null) {
       CollectionUtils.filter(setByHost, new Predicate() {
@@ -244,8 +240,7 @@ public class ConfigGroupHostMappingDAO {
     
     entityManagerProvider.get().remove(findByPK(configGroupHostMappingEntityPK));
     
-    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost
-      .get(configGroupHostMappingEntityPK.getHostname());
+    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get(configGroupHostMappingEntityPK.getHostId());
     
     if (setByHost != null) {
       CollectionUtils.filter(setByHost, new Predicate() {
@@ -287,19 +282,17 @@ public class ConfigGroupHostMappingDAO {
   }
 
   @Transactional
-  public void removeAllByHost(String hostname) {
+  public void removeAllByHost(Long hostId) {
     TypedQuery<String> query = entityManagerProvider.get().createQuery
       ("DELETE FROM ConfigGroupHostMappingEntity confighosts WHERE " +
-        "confighosts.hostname = ?1", String.class);
+        "confighosts.hostId = ?1", String.class);
 
-    daoUtils.executeUpdate(query, hostname);
+    daoUtils.executeUpdate(query, hostId);
     
     
-    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get(hostname);
+    Set<ConfigGroupHostMapping> setByHost = configGroupHostMappingByHost.get(hostId);
     
     setByHost.clear();
-    
-    
   }
   
   private ConfigGroupHostMapping buildConfigGroupHostMapping(
@@ -309,13 +302,12 @@ public class ConfigGroupHostMappingDAO {
     configGroupHostMapping.setConfigGroup(buildConfigGroup(configGroupHostMappingEntity.getConfigGroupEntity()));
     configGroupHostMapping.setConfigGroupId(configGroupHostMappingEntity.getConfigGroupId());
     configGroupHostMapping.setHost(buildHost(configGroupHostMappingEntity.getHostEntity()));
-    configGroupHostMapping.setHostname(configGroupHostMappingEntity.getHostname());
+    configGroupHostMapping.setHostId(configGroupHostMappingEntity.getHostId());
     
     return configGroupHostMapping;
   }
 
   private ConfigGroup buildConfigGroup(ConfigGroupEntity configGroupEntity) {
-    
     Cluster cluster = clusterFactory.create(configGroupEntity.getClusterEntity());
     ConfigGroup configGroup = configGroupFactory.createExisting(cluster, configGroupEntity);
     
@@ -323,9 +315,7 @@ public class ConfigGroupHostMappingDAO {
   }
 
   private Host buildHost(HostEntity hostEntity) {
-    
     Host host = hostFactory.create(hostEntity, false);
-    
     return host;
   }
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostConfigMappingDAO.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostConfigMappingDAO.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostConfigMappingDAO.java
index 9bc1235..34d0e3c 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostConfigMappingDAO.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostConfigMappingDAO.java
@@ -17,7 +17,15 @@
  */
 package org.apache.ambari.server.orm.dao;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.WeakHashMap;
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
@@ -30,6 +38,7 @@ import org.apache.ambari.server.orm.RequiresSession;
 import org.apache.ambari.server.orm.cache.HostConfigMapping;
 import org.apache.ambari.server.orm.cache.HostConfigMappingImpl;
 import org.apache.ambari.server.orm.entities.HostConfigMappingEntity;
+import org.apache.ambari.server.orm.entities.HostEntity;
 import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.collections.Predicate;
 
@@ -43,13 +52,16 @@ import com.google.inject.persist.Transactional;
 @Singleton
 public class HostConfigMappingDAO {
   @Inject
-  Provider<EntityManager> entityManagerProvider;
+  private Provider<EntityManager> entityManagerProvider;
+
   @Inject
-  DaoUtils daoUtils;
-  
+  private DaoUtils daoUtils;
+
+  @Inject
+  private HostDAO hostDAO;
 
   private final ReadWriteLock gl = new ReentrantReadWriteLock();
-  private Map<String, Set<HostConfigMapping>> hostConfigMappingByHost;
+  private Map<Long, Set<HostConfigMapping>> hostConfigMappingByHost;
   
   private volatile boolean cacheLoaded;
   
@@ -61,7 +73,7 @@ public class HostConfigMappingDAO {
         gl.writeLock().lock();
         try {
           if (hostConfigMappingByHost == null) {
-            hostConfigMappingByHost = new WeakHashMap<String, Set<HostConfigMapping>>();
+            hostConfigMappingByHost = new WeakHashMap<Long, Set<HostConfigMapping>>();
             
             TypedQuery<HostConfigMappingEntity> query = entityManagerProvider.get().createQuery(
                 "SELECT entity FROM HostConfigMappingEntity entity",
@@ -70,12 +82,18 @@ public class HostConfigMappingDAO {
             List<HostConfigMappingEntity> hostConfigMappingEntities = daoUtils.selectList(query);
             
             for (HostConfigMappingEntity hostConfigMappingEntity : hostConfigMappingEntities) {
+              Long hostId = hostConfigMappingEntity.getHostId();
 
-              Set<HostConfigMapping> setByHost = hostConfigMappingByHost.get((hostConfigMappingEntity.getHostName()));
-              
-              if (setByHost == null) {
+              if (hostId == null) {
+                continue;
+              }
+
+              Set<HostConfigMapping> setByHost;
+              if (hostConfigMappingByHost.containsKey(hostId)) {
+                setByHost = hostConfigMappingByHost.get(hostId);
+              } else {
                 setByHost = new HashSet<HostConfigMapping>();
-                hostConfigMappingByHost.put(hostConfigMappingEntity.getHostName(), setByHost);
+                hostConfigMappingByHost.put(hostId, setByHost);
               }
        
               HostConfigMapping hostConfigMapping = buildHostConfigMapping(hostConfigMappingEntity);
@@ -90,65 +108,70 @@ public class HostConfigMappingDAO {
       }
       
       cacheLoaded = true;
-
     }
-    
   }
   
 
   @Transactional
   public void create(HostConfigMapping hostConfigMapping) {
-    
     populateCache();
     
     //create in db
     entityManagerProvider.get().persist(buildHostConfigMappingEntity(hostConfigMapping));
     
     //create in cache
-    Set<HostConfigMapping> set = hostConfigMappingByHost.get(hostConfigMapping.getHostName());
-    if (set == null){
-      set = new HashSet<HostConfigMapping>();
-      hostConfigMappingByHost.put(hostConfigMapping.getHostName(), set);
+    Long hostId = hostConfigMapping.getHostId();
+
+    if (hostId != null) {
+      Set<HostConfigMapping> set;
+      if (hostConfigMappingByHost.containsKey(hostId)) {
+        set = hostConfigMappingByHost.get(hostId);
+      } else {
+        set = new HashSet<HostConfigMapping>();
+        hostConfigMappingByHost.put(hostId, set);
+      }
+
+      set.add(hostConfigMapping);
     }
-    
-    set.add(hostConfigMapping);
   }
 
   @Transactional
   public HostConfigMapping merge(HostConfigMapping hostConfigMapping) {
-    
     populateCache();
-    
-    Set<HostConfigMapping> set = hostConfigMappingByHost.get(hostConfigMapping.getHostName());
-    if (set == null){
-      set = new HashSet<HostConfigMapping>();
-      hostConfigMappingByHost.put(hostConfigMapping.getHostName(), set);
+
+    Long hostId = hostConfigMapping.getHostId();
+    if (hostId != null) {
+      Set<HostConfigMapping> set;
+      if (hostConfigMappingByHost.containsKey(hostId)) {
+        set = hostConfigMappingByHost.get(hostId);
+      } else {
+        set = new HashSet<HostConfigMapping>();
+        hostConfigMappingByHost.put(hostId, set);
+      }
+
+      //Update object in set
+      set.remove(hostConfigMapping);
+      set.add(hostConfigMapping);
+
+      entityManagerProvider.get().merge(buildHostConfigMappingEntity(hostConfigMapping));
     }
-    
-    //Update object in set
-    set.remove(hostConfigMapping);
-    set.add(hostConfigMapping);
-    
-    entityManagerProvider.get().merge(buildHostConfigMappingEntity(hostConfigMapping));
-    
+
     return hostConfigMapping;
   }
 
   @RequiresSession
-  public Set<HostConfigMapping> findByType(final long clusterId, String hostName, final String type) {
-    
+  public Set<HostConfigMapping> findByType(final long clusterId, Long hostId, final String type) {
     populateCache();
     
-    if (!hostConfigMappingByHost.containsKey(hostName))
+    if (!hostConfigMappingByHost.containsKey(hostId))
       return Collections.emptySet();
       
-    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostName));
+    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostId));
      
     CollectionUtils.filter(set, new Predicate() {
         
       @Override
       public boolean evaluate(Object arg0) {
-                  
         return ((HostConfigMapping) arg0).getClusterId().equals(clusterId) 
             && ((HostConfigMapping) arg0).getType().equals(type);
       }
@@ -159,41 +182,35 @@ public class HostConfigMappingDAO {
 
   @RequiresSession
   public HostConfigMapping findSelectedByType(final long clusterId,
-      String hostName, final String type) {
-    
+      Long hostId, final String type) {
     populateCache();
     
-    if (!hostConfigMappingByHost.containsKey(hostName))
+    if (!hostConfigMappingByHost.containsKey(hostId))
       return null;
     
-    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostName));
+    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostId));
     
     HostConfigMapping result = (HostConfigMapping) CollectionUtils.find(set, new Predicate() {
       
       @Override
       public boolean evaluate(Object arg0) {
-        
         return ((HostConfigMapping) arg0).getClusterId().equals(clusterId) 
             && ((HostConfigMapping) arg0).getType().equals(type)
             && ((HostConfigMapping) arg0).getSelected() > 0;
       }
     });
     
-    
     return result;
-    
   }
 
   @RequiresSession
-  public Set<HostConfigMapping> findSelected(final long clusterId, String hostName) {
-    
+  public Set<HostConfigMapping> findSelected(final long clusterId, Long hostId) {
     populateCache();
     
-    if (!hostConfigMappingByHost.containsKey(hostName))
+    if (!hostConfigMappingByHost.containsKey(hostId))
       return Collections.emptySet();
-      
     
-    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostName));
+    Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostId));
     
     CollectionUtils.filter(set, new Predicate() {
       
@@ -208,31 +225,26 @@ public class HostConfigMappingDAO {
   }
 
   @RequiresSession
-  public Set<HostConfigMapping> findSelectedByHosts(long clusterId, Collection<String> hostNames) {
-    
+  public Set<HostConfigMapping> findSelectedByHosts(Collection<Long> hostIds) {
     populateCache();
 
-    if (hostNames == null || hostNames.isEmpty()) {
+    if (hostIds == null || hostIds.isEmpty()) {
       return Collections.emptySet();
     }
     
-    
     HashSet<HostConfigMapping> result = new HashSet<HostConfigMapping>();
-    
-
 
-    for (final String hostName : hostNames) {
-      
-      if (!hostConfigMappingByHost.containsKey(hostName))
+    for (final Long hostId : hostIds) {
+      if (!hostConfigMappingByHost.containsKey(hostId))
         continue;
       
-      Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostName));
+      Set<HostConfigMapping> set = new HashSet<HostConfigMapping>(hostConfigMappingByHost.get(hostId));
       
       CollectionUtils.filter(set, new Predicate() {
         
         @Override
         public boolean evaluate(Object arg0) {
-          return ((HostConfigMapping) arg0).getHostName().equals(hostName) && 
+          return ((HostConfigMapping) arg0).getHostId().equals(hostId) &&
               ((HostConfigMapping) arg0).getSelected() > 0;
         }
       });
@@ -247,9 +259,7 @@ public class HostConfigMappingDAO {
   @RequiresSession
   public Map<String, List<HostConfigMapping>> findSelectedHostsByTypes(final long clusterId,
                                                                              Collection<String> types) {
-    
     populateCache();
-
     
     Map<String, List<HostConfigMapping>> mappingsByType = new HashMap<String, List<HostConfigMapping>>();
     
@@ -268,7 +278,6 @@ public class HostConfigMappingDAO {
           
           if (types.contains(entry.getType()) && entry.getClusterId().equals(clusterId))
             mappings.add(new HostConfigMappingImpl(entry));
-          
         }
       }
 
@@ -276,8 +285,6 @@ public class HostConfigMappingDAO {
         mappingsByType.get(mapping.getType()).add(mapping);
       }
     }
-    
-    
 
     return mappingsByType;
   }
@@ -293,42 +300,40 @@ public class HostConfigMappingDAO {
    */
   @Transactional
   public void removeHost(final long clusterId, String hostName) {
-    
     populateCache();
-    
-    Set<HostConfigMapping> set = hostConfigMappingByHost.get(hostName);
-    
-    //Remove from cache items with clusterId
-    CollectionUtils.filter(set, new Predicate() {
-      
-      @Override
-      public boolean evaluate(Object arg0) {
-        return !((HostConfigMapping) arg0).getClusterId().equals(clusterId);
+
+    if (hostConfigMappingByHost.containsKey(hostName)) {
+      Set<HostConfigMapping> set = hostConfigMappingByHost.get(hostName);
+
+      //Remove from cache items with clusterId
+      CollectionUtils.filter(set, new Predicate() {
+        @Override
+        public boolean evaluate(Object arg0) {
+          return !((HostConfigMapping) arg0).getClusterId().equals(clusterId);
+        }
+      });
+
+      //delete from db
+      TypedQuery<HostConfigMappingEntity> query = entityManagerProvider.get().createQuery(
+          "SELECT entity FROM HostConfigMappingEntity entity " +
+              "WHERE entity.clusterId = ?1 AND entity.hostEntity.hostName = ?2",
+          HostConfigMappingEntity.class);
+
+      List<HostConfigMappingEntity> list = daoUtils.selectList(query, Long.valueOf(clusterId), hostName);
+
+      for (HostConfigMappingEntity entity : list) {
+        entityManagerProvider.get().remove(entity);
       }
-    });
-    
-    //delete from db
-    TypedQuery<HostConfigMappingEntity> query = entityManagerProvider.get().createQuery(
-      "SELECT entity FROM HostConfigMappingEntity entity " +
-      "WHERE entity.clusterId = ?1 AND entity.hostName = ?2",
-      HostConfigMappingEntity.class);
-             
-    List<HostConfigMappingEntity> list = daoUtils.selectList(query, Long.valueOf(clusterId), hostName);
-        
-    for (HostConfigMappingEntity entity : list) {
-      entityManagerProvider.get().remove(entity);
     }
-    
-    
   }
 
   public HostConfigMappingEntity buildHostConfigMappingEntity(HostConfigMapping hostConfigMapping) {
-    
+    HostEntity hostEntity = hostDAO.findById(hostConfigMapping.getHostId());
     HostConfigMappingEntity hostConfigMappingEntity = new HostConfigMappingEntity();
-    
+
     hostConfigMappingEntity.setClusterId(hostConfigMapping.getClusterId());
     hostConfigMappingEntity.setCreateTimestamp(hostConfigMapping.getCreateTimestamp());
-    hostConfigMappingEntity.setHostName(hostConfigMapping.getHostName());
+    hostConfigMappingEntity.setHostId(hostEntity.getHostId());
     hostConfigMappingEntity.setSelected(hostConfigMapping.getSelected());
     hostConfigMappingEntity.setServiceName(hostConfigMapping.getServiceName());
     hostConfigMappingEntity.setType(hostConfigMapping.getType());
@@ -340,12 +345,11 @@ public class HostConfigMappingDAO {
   
   public HostConfigMapping buildHostConfigMapping(
       HostConfigMappingEntity hostConfigMappingEntity) {
-    
     HostConfigMapping hostConfigMapping = new HostConfigMappingImpl();
     
     hostConfigMapping.setClusterId(hostConfigMappingEntity.getClusterId());
     hostConfigMapping.setCreateTimestamp(hostConfigMappingEntity.getCreateTimestamp());
-    hostConfigMapping.setHostName(hostConfigMappingEntity.getHostName());
+    hostConfigMapping.setHostId(hostConfigMappingEntity.getHostId());
     hostConfigMapping.setServiceName(hostConfigMappingEntity.getServiceName());
     hostConfigMapping.setType(hostConfigMappingEntity.getType());
     hostConfigMapping.setUser(hostConfigMappingEntity.getUser());
@@ -354,5 +358,4 @@ public class HostConfigMappingDAO {
     
     return hostConfigMapping;
   }
-
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostDAO.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostDAO.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostDAO.java
index 6442bf5..ebd29e3 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostDAO.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/dao/HostDAO.java
@@ -29,6 +29,7 @@ import org.apache.ambari.server.orm.entities.StageEntity;
 import javax.persistence.EntityManager;
 import javax.persistence.NoResultException;
 import javax.persistence.TypedQuery;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
@@ -117,4 +118,14 @@ public class HostDAO {
     remove(findByName(hostName));
   }
 
+  public List<String> getHostNamesByHostIds(List<Long> hostIds) {
+    List<String> hostNames = new ArrayList<String>();
+    if (hostIds != null) {
+      for (Long hostId : hostIds) {
+        HostEntity hostEntity = findById(hostId);
+        hostNames.add(hostEntity.getHostName());
+      }
+    }
+    return hostNames;
+  }
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntity.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntity.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntity.java
index 261bbe8..a9a2d40 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntity.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntity.java
@@ -34,7 +34,7 @@ import javax.persistence.Table;
 @NamedQueries({
   @NamedQuery(name = "groupsByHost", query =
   "SELECT confighosts FROM ConfigGroupHostMappingEntity confighosts " +
-    "WHERE confighosts.hostname=:hostname"),
+    "WHERE confighosts.hostEntity.hostName=:hostname"),
   @NamedQuery(name = "hostsByGroup", query =
   "SELECT confighosts FROM ConfigGroupHostMappingEntity confighosts " +
     "WHERE confighosts.configGroupId=:groupId")
@@ -46,12 +46,12 @@ public class ConfigGroupHostMappingEntity {
   private Long configGroupId;
 
   @Id
-  @Column(name = "host_name", nullable = false, insertable = true, updatable = true)
-  private String hostname;
+  @Column(name = "host_id", nullable = false, insertable = true, updatable = true)
+  private Long hostId;
 
   @ManyToOne
   @JoinColumns({
-    @JoinColumn(name = "host_name", referencedColumnName = "host_name", nullable = false, insertable = false, updatable = false) })
+    @JoinColumn(name = "host_id", referencedColumnName = "host_id", nullable = false, insertable = false, updatable = false) })
   private HostEntity hostEntity;
 
   @ManyToOne
@@ -67,12 +67,16 @@ public class ConfigGroupHostMappingEntity {
     this.configGroupId = configGroupId;
   }
 
-  public String getHostname() {
-    return hostname;
+  public Long getHostId() {
+    return hostId;
+  }
+
+  public void setHostId(Long hostId) {
+    this.hostId = hostId;
   }
 
-  public void setHostname(String hostname) {
-    this.hostname = hostname;
+  public String getHostname() {
+    return hostEntity != null ? hostEntity.getHostName() : null;
   }
 
   public HostEntity getHostEntity() {
@@ -99,7 +103,7 @@ public class ConfigGroupHostMappingEntity {
     ConfigGroupHostMappingEntity that = (ConfigGroupHostMappingEntity) o;
 
     if (!configGroupId.equals(that.configGroupId)) return false;
-    if (!hostname.equals(that.hostname)) return false;
+    if (!hostEntity.equals(that.hostEntity)) return false;
 
     return true;
   }
@@ -107,7 +111,7 @@ public class ConfigGroupHostMappingEntity {
   @Override
   public int hashCode() {
     int result = configGroupId.hashCode();
-    result = 31 * result + hostname.hashCode();
+    result = 31 * result + hostEntity.hashCode();
     return result;
   }
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntityPK.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntityPK.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntityPK.java
index 3ee2b6c..e7ed99e 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntityPK.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ConfigGroupHostMappingEntityPK.java
@@ -23,7 +23,7 @@ import java.io.Serializable;
 
 public class ConfigGroupHostMappingEntityPK implements Serializable {
   private Long configGroupId;
-  private String hostname;
+  private Long hostId;
 
   @Id
   @Column(name = "config_group_id", nullable = false, insertable = true, updatable = true)
@@ -36,13 +36,13 @@ public class ConfigGroupHostMappingEntityPK implements Serializable {
   }
 
   @Id
-  @Column(name = "host_name", nullable = false, insertable = true, updatable = true)
-  public String getHostname() {
-    return hostname;
+  @Column(name = "host_id", nullable = false, insertable = true, updatable = true)
+  public Long getHostId() {
+    return hostId;
   }
 
-  public void setHostname(String hostname) {
-    this.hostname = hostname;
+  public void setHostId(Long hostId) {
+    this.hostId = hostId;
   }
 
   @Override
@@ -53,7 +53,7 @@ public class ConfigGroupHostMappingEntityPK implements Serializable {
     ConfigGroupHostMappingEntityPK that = (ConfigGroupHostMappingEntityPK) o;
 
     if (!configGroupId.equals(that.configGroupId)) return false;
-    if (!hostname.equals(that.hostname)) return false;
+    if (!hostId.equals(that.hostId)) return false;
 
     return true;
   }
@@ -61,7 +61,7 @@ public class ConfigGroupHostMappingEntityPK implements Serializable {
   @Override
   public int hashCode() {
     int result = configGroupId.hashCode();
-    result = 31 * result + hostname.hashCode();
+    result = 31 * result + hostId.hashCode();
     return result;
   }
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntity.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntity.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntity.java
index 1411a67..915b05f 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntity.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntity.java
@@ -36,8 +36,8 @@ public class HostConfigMappingEntity {
   private Long clusterId;
 
   @Id
-  @Column(name = "host_name", insertable = true, updatable = false, nullable = false)
-  private String hostName;
+  @Column(name = "host_id", insertable = true, updatable = false, nullable=false)
+  private Long hostId;
 
   @Id
   @Column(name = "type_name", insertable = true, updatable = false, nullable = false)
@@ -58,7 +58,7 @@ public class HostConfigMappingEntity {
   
   @Column(name = "user_name", insertable = true, updatable = true, nullable = false)
   private String user = null;
-  
+
   public Long getClusterId() {
     return clusterId;
   }
@@ -67,12 +67,12 @@ public class HostConfigMappingEntity {
     clusterId = id;
   }
 
-  public String getHostName() {
-    return hostName;
+  public Long getHostId() {
+    return hostId;
   }
 
-  public void setHostName(String name) {
-    hostName = name;
+  public void setHostId(Long hostId) {
+    this.hostId = hostId;
   }
 
   public String getType() {
@@ -140,7 +140,7 @@ public class HostConfigMappingEntity {
     if (clusterId != null ? !clusterId.equals(that.clusterId) : that.clusterId != null) return false;
     if (createTimestamp != null ? !createTimestamp.equals(that.createTimestamp) : that.createTimestamp != null)
       return false;
-    if (hostName != null ? !hostName.equals(that.hostName) : that.hostName != null) return false;
+    if (hostId != null ? !hostId.equals(that.hostId) : that.hostId != null) return false;
     if (serviceName != null ? !serviceName.equals(that.serviceName) : that.serviceName != null) return false;
     if (type != null ? !type.equals(that.type) : that.type != null) return false;
     if (user != null ? !user.equals(that.user) : that.user != null) return false;
@@ -152,7 +152,7 @@ public class HostConfigMappingEntity {
   @Override
   public int hashCode() {
     int result = clusterId != null ? clusterId.hashCode() : 0;
-    result = 31 * result + (hostName != null ? hostName.hashCode() : 0);
+    result = 31 * result + (hostId != null ? hostId.hashCode() : 0);
     result = 31 * result + (type != null ? type.hashCode() : 0);
     result = 31 * result + (createTimestamp != null ? createTimestamp.hashCode() : 0);
     result = 31 * result + (versionTag != null ? versionTag.hashCode() : 0);

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntityPK.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntityPK.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntityPK.java
index 16111fb..61039bb 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntityPK.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/HostConfigMappingEntityPK.java
@@ -27,7 +27,7 @@ import java.io.Serializable;
  */
 public class HostConfigMappingEntityPK implements Serializable {
   private Long clusterId;
-  private String hostName;
+  private Long hostId;
   private String type;
   private Long createTimestamp;
 
@@ -41,14 +41,14 @@ public class HostConfigMappingEntityPK implements Serializable {
     clusterId = id;
   }
   
-  @Column(name = "host_name", insertable = true, updatable = true, nullable = false)
+  @Column(name = "host_id", insertable = true, updatable = true, nullable = false)
   @Id
-  public String getHostName() {
-    return hostName;
+  public Long getHostId() {
+    return hostId;
   }
   
-  public void setHostName(String name) {
-    hostName = name;
+  public void setHostId(Long hostId) {
+    this.hostId = hostId;
   }
   
   @Column(name = "type_name", insertable = true, updatable = true, nullable = false)
@@ -81,7 +81,7 @@ public class HostConfigMappingEntityPK implements Serializable {
     HostConfigMappingEntityPK that = (HostConfigMappingEntityPK) o;
 
     if (clusterId != null ? !clusterId.equals(that.clusterId) : that.clusterId != null) return false;
-    if (hostName != null ? !hostName.equals(that.hostName) : that.hostName != null) return false;
+    if (hostId != null ? !hostId.equals(that.hostId) : that.hostId != null) return false;
     if (type != null ? !type.equals(that.type) : that.type != null) return false;
     if (createTimestamp != null ? !createTimestamp.equals (that.createTimestamp) : that.createTimestamp != null) return false;
 
@@ -92,10 +92,8 @@ public class HostConfigMappingEntityPK implements Serializable {
   public int hashCode() {
     int result = clusterId !=null ? clusterId.intValue() : 0;
     result = 31 * result + (type != null ? type.hashCode() : 0);
-    result = 31 * result + (hostName != null ? hostName.hashCode() : 0);
+    result = 31 * result + (hostId != null ? hostId.hashCode() : 0);
     result = 31 * result + createTimestamp.intValue();
     return result;
-  }  
-  
-  
+  }
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ServiceConfigEntity.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ServiceConfigEntity.java b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ServiceConfigEntity.java
index 1a31252..cd3bb54 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ServiceConfigEntity.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/orm/entities/ServiceConfigEntity.java
@@ -83,8 +83,8 @@ public class ServiceConfigEntity {
 
   @ElementCollection()
   @CollectionTable(name = "serviceconfighosts", joinColumns = {@JoinColumn(name = "service_config_id")})
-  @Column(name = "hostname")
-  private List<String> hostNames;
+  @Column(name = "host_id")
+  private List<Long> hostIds;
 
   @ManyToMany
   @JoinTable(
@@ -185,12 +185,12 @@ public class ServiceConfigEntity {
     this.groupId = groupId;
   }
 
-  public List<String> getHostNames() {
-    return hostNames;
+  public List<Long> getHostIds() {
+    return hostIds;
   }
 
-  public void setHostNames(List<String> hostNames) {
-    this.hostNames = hostNames;
+  public void setHostIds(List<Long> hostIds) {
+    this.hostIds = hostIds;
   }
 
   /**

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/Cluster.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/Cluster.java b/ambari-server/src/main/java/org/apache/ambari/server/state/Cluster.java
index 855bb3f..209293f 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/Cluster.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/Cluster.java
@@ -406,16 +406,16 @@ public interface Cluster {
 
   /**
    * Fetch desired configs for list of hosts in cluster
-   * @param hostnames
+   * @param hostIds
    * @return
    */
-  Map<String, Map<String, DesiredConfig>> getHostsDesiredConfigs(Collection<String> hostnames);
+  Map<Long, Map<String, DesiredConfig>> getHostsDesiredConfigs(Collection<Long> hostIds);
 
   /**
    * Fetch desired configs for all hosts in cluster
    * @return
    */
-  Map<String, Map<String, DesiredConfig>> getAllHostsDesiredConfigs();
+  Map<Long, Map<String, DesiredConfig>> getAllHostsDesiredConfigs();
 
   /**
    * Add a new config group to the set of Config groups associated with this

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/Clusters.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/Clusters.java b/ambari-server/src/main/java/org/apache/ambari/server/state/Clusters.java
index 80ac6a7..6edf7d9 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/Clusters.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/Clusters.java
@@ -80,6 +80,14 @@ public interface Clusters {
   public Host getHost(String hostname) throws AmbariException;
 
   /**
+   * Get a Host object managed by this server
+   * @param hostId Host Id from the {@link org.apache.ambari.server.orm.entities.HostEntity} objecty
+   * @return Host object
+   * @throws AmbariException
+   */
+  public Host getHostById(Long hostId) throws AmbariException;
+
+  /**
    * Add a Host object to be managed by this server
    * @param hostname Host to be added
    * @throws AmbariException
@@ -137,6 +145,15 @@ public interface Clusters {
       throws AmbariException;
 
   /**
+   * Gets all the host Ids associated with the cluster
+   * @param clusterName The name of the cluster
+   * @return <code>Map</code> containing host id and <code>Host</code>
+   * @throws AmbariException
+   */
+  public Map<Long, Host> getHostIdsForCluster(String clusterName)
+      throws AmbariException;
+
+  /**
    * Deletes the cluster identified by the name
    * @param clusterName The name of the cluster
    * @throws AmbariException

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java
index 2558de8..bb6f6c1 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClusterImpl.java
@@ -290,7 +290,6 @@ public class ClusterImpl implements Cluster {
     return clusterGlobalLock;
   }
 
-
   private void loadServiceConfigTypes() throws AmbariException {
     try {
       serviceConfigTypes = collectServiceConfigTypesMapping();
@@ -501,22 +500,24 @@ public class ClusterImpl implements Cluster {
 
     clusterGlobalLock.readLock().lock();
     try {
-      Set<ConfigGroupHostMapping> hostMappingEntities = configGroupHostMappingDAO.findByHost(hostname);
-
-      if (hostMappingEntities != null && !hostMappingEntities.isEmpty()) {
-        for (ConfigGroupHostMapping entity : hostMappingEntities) {
-          ConfigGroup configGroup = configGroupMap.get(entity.getConfigGroupId());
-          if (configGroup != null
-              && !configGroups.containsKey(configGroup.getId())) {
-            configGroups.put(configGroup.getId(), configGroup);
+      HostEntity hostEntity = hostDAO.findByName(hostname);
+      if (hostEntity != null) {
+        Set<ConfigGroupHostMapping> hostMappingEntities = configGroupHostMappingDAO.findByHostId(hostEntity.getHostId());
+
+        if (hostMappingEntities != null && !hostMappingEntities.isEmpty()) {
+          for (ConfigGroupHostMapping entity : hostMappingEntities) {
+            ConfigGroup configGroup = configGroupMap.get(entity.getConfigGroupId());
+            if (configGroup != null
+                && !configGroups.containsKey(configGroup.getId())) {
+              configGroups.put(configGroup.getId(), configGroup);
+            }
           }
         }
       }
-      return configGroups;
-
     } finally {
       clusterGlobalLock.readLock().unlock();
     }
+    return configGroups;
   }
 
   @Override
@@ -1964,6 +1965,9 @@ public class ClusterImpl implements Cluster {
         }
       }
 
+      // TODO AMBARI-10679, need efficient caching from hostId to hostName
+      Map<Long, String> hostIdToName = new HashMap<Long, String>();
+
       if (!map.isEmpty()) {
         Map<String, List<HostConfigMapping>> hostMappingsByType = hostConfigMappingDAO.findSelectedHostsByTypes(
             clusterEntity.getClusterId(), types);
@@ -1971,8 +1975,14 @@ public class ClusterImpl implements Cluster {
         for (Entry<String, DesiredConfig> entry : map.entrySet()) {
           List<DesiredConfig.HostOverride> hostOverrides = new ArrayList<DesiredConfig.HostOverride>();
           for (HostConfigMapping mappingEntity : hostMappingsByType.get(entry.getKey())) {
+
+            if (!hostIdToName.containsKey(mappingEntity.getHostId())) {
+              HostEntity hostEntity = hostDAO.findById(mappingEntity.getHostId());
+              hostIdToName.put(mappingEntity.getHostId(), hostEntity.getHostName());
+            }
+
             hostOverrides.add(new DesiredConfig.HostOverride(
-                mappingEntity.getHostName(), mappingEntity.getVersion()));
+                hostIdToName.get(mappingEntity.getHostId()), mappingEntity.getVersion()));
           }
           entry.getValue().setHostOverrides(hostOverrides);
         }
@@ -2002,7 +2012,7 @@ public class ClusterImpl implements Cluster {
       }
 
       serviceConfigEntity.setClusterConfigEntities(configEntities);
-      serviceConfigEntity.setHostNames(new ArrayList<String>(configGroup.getHosts().keySet()));
+      serviceConfigEntity.setHostIds(new ArrayList<Long>(configGroup.getHosts().keySet()));
 
     } else {
       List<ClusterConfigEntity> configEntities = getClusterConfigEntitiesByService(serviceName);
@@ -2248,13 +2258,15 @@ public class ClusterImpl implements Cluster {
         }
         configGroup.setConfigurations(groupDesiredConfigs);
 
-        Map<String, Host> groupDesiredHosts = new HashMap<String, Host>();
-        for (String hostname : serviceConfigEntity.getHostNames()) {
-          Host host = clusters.getHost(hostname);
-          if (host != null) {
-            groupDesiredHosts.put(hostname, host);
-          } else {
-            LOG.warn("Host {} doesn't exist anymore, skipping", hostname);
+        Map<Long, Host> groupDesiredHosts = new HashMap<Long, Host>();
+        if (serviceConfigEntity.getHostIds() != null) {
+          for (Long hostId : serviceConfigEntity.getHostIds()) {
+            Host host = clusters.getHostById(hostId);
+            if (host != null) {
+              groupDesiredHosts.put(hostId, host);
+            } else {
+              LOG.warn("Host with id {} doesn't exist anymore, skipping", hostId);
+            }
           }
         }
         configGroup.setHosts(groupDesiredHosts);
@@ -2275,7 +2287,7 @@ public class ClusterImpl implements Cluster {
     serviceConfigEntityClone.setStack(serviceConfigEntity.getStack());
     serviceConfigEntityClone.setClusterConfigEntities(serviceConfigEntity.getClusterConfigEntities());
     serviceConfigEntityClone.setClusterId(serviceConfigEntity.getClusterId());
-    serviceConfigEntityClone.setHostNames(serviceConfigEntity.getHostNames());
+    serviceConfigEntityClone.setHostIds(serviceConfigEntity.getHostIds());
     serviceConfigEntityClone.setGroupId(serviceConfigEntity.getGroupId());
     serviceConfigEntityClone.setNote(serviceConfigVersionNote);
     serviceConfigEntityClone.setVersion(nextServiceConfigVersion);
@@ -2388,21 +2400,20 @@ public class ClusterImpl implements Cluster {
     }
   }
 
-
   @Override
-  public Map<String, Map<String, DesiredConfig>> getHostsDesiredConfigs(Collection<String> hostnames) {
+  public Map<Long, Map<String, DesiredConfig>> getHostsDesiredConfigs(Collection<Long> hostIds) {
 
-    if (hostnames == null || hostnames.isEmpty()) {
+    if (hostIds == null || hostIds.isEmpty()) {
       return Collections.emptyMap();
     }
 
     Set<HostConfigMapping> mappingEntities =
-      hostConfigMappingDAO.findSelectedByHosts(clusterEntity.getClusterId(), hostnames);
+        hostConfigMappingDAO.findSelectedByHosts(hostIds);
 
-    Map<String, Map<String, DesiredConfig>> desiredConfigsByHost = new HashMap<String, Map<String, DesiredConfig>>();
+    Map<Long, Map<String, DesiredConfig>> desiredConfigsByHost = new HashMap<Long, Map<String, DesiredConfig>>();
 
-    for (String hostname : hostnames) {
-      desiredConfigsByHost.put(hostname, new HashMap<String, DesiredConfig>());
+    for (Long hostId : hostIds) {
+      desiredConfigsByHost.put(hostId, new HashMap<String, DesiredConfig>());
     }
 
     for (HostConfigMapping mappingEntity : mappingEntities) {
@@ -2411,23 +2422,23 @@ public class ClusterImpl implements Cluster {
       desiredConfig.setServiceName(mappingEntity.getServiceName());
       desiredConfig.setUser(mappingEntity.getUser());
 
-      desiredConfigsByHost.get(mappingEntity.getHostName()).put(mappingEntity.getType(), desiredConfig);
+      desiredConfigsByHost.get(mappingEntity.getHostId()).put(mappingEntity.getType(), desiredConfig);
     }
 
     return desiredConfigsByHost;
   }
 
   @Override
-  public Map<String, Map<String, DesiredConfig>> getAllHostsDesiredConfigs() {
+  public Map<Long, Map<String, DesiredConfig>> getAllHostsDesiredConfigs() {
 
-    Collection<String> hostnames;
+    Collection<Long> hostIds;
     try {
-      hostnames = clusters.getHostsForCluster(clusterEntity.getClusterName()).keySet();
+      hostIds = clusters.getHostIdsForCluster(clusterEntity.getClusterName()).keySet();
     } catch (AmbariException ignored) {
       return Collections.emptyMap();
     }
 
-    return getHostsDesiredConfigs(hostnames);
+    return getHostsDesiredConfigs(hostIds);
   }
 
   /**

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
index 70788ff..f8066ca 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/cluster/ClustersImpl.java
@@ -89,6 +89,7 @@ public class ClustersImpl implements Clusters {
   private ConcurrentHashMap<String, Cluster> clusters;
   private ConcurrentHashMap<Long, Cluster> clustersById;
   private ConcurrentHashMap<String, Host> hosts;
+  private ConcurrentHashMap<Long, Host> hostsById;
   private ConcurrentHashMap<String, Set<Cluster>> hostClusterMap;
   private ConcurrentHashMap<String, Set<Host>> clusterHostMap;
 
@@ -138,6 +139,7 @@ public class ClustersImpl implements Clusters {
     clusters = new ConcurrentHashMap<String, Cluster>();
     clustersById = new ConcurrentHashMap<Long, Cluster>();
     hosts = new ConcurrentHashMap<String, Host>();
+    hostsById = new ConcurrentHashMap<Long, Host>();
     hostClusterMap = new ConcurrentHashMap<String, Set<Cluster>>();
     clusterHostMap = new ConcurrentHashMap<String, Set<Host>>();
 
@@ -172,6 +174,7 @@ public class ClustersImpl implements Clusters {
     for (HostEntity hostEntity : hostDAO.findAll()) {
       Host host = hostFactory.create(hostEntity, true);
       hosts.put(hostEntity.getHostName(), host);
+      hostsById.put(hostEntity.getHostId(), host);
       Set<Cluster> cSet = Collections.newSetFromMap(new ConcurrentHashMap<Cluster, Boolean>());
       hostClusterMap.put(hostEntity.getHostName(), cSet);
 
@@ -328,6 +331,17 @@ public class ClustersImpl implements Clusters {
     return hosts.get(hostname);
   }
 
+  @Override
+  public Host getHostById(Long hostId) throws AmbariException {
+    checkLoaded();
+
+    if (!hosts.containsKey(hostId)) {
+      throw new HostNotFoundException("Host Id = " + hostId);
+    }
+
+    return hosts.get(hostId);
+  }
+
   /**
    * Register a host by creating a {@link HostEntity} object in the database and setting its state to
    * {@link HostState#INIT}. This does not add the host the cluster.
@@ -614,6 +628,27 @@ public class ClustersImpl implements Clusters {
   }
 
   @Override
+  public Map<Long, Host> getHostIdsForCluster(String clusterName)
+      throws AmbariException {
+
+    checkLoaded();
+    r.lock();
+
+    try {
+      Map<Long, Host> hosts = new HashMap<Long, Host>();
+
+      for (Host h : clusterHostMap.get(clusterName)) {
+        HostEntity hostEntity = hostDAO.findByName(h.getHostName());
+        hosts.put(hostEntity.getHostId(), h);
+      }
+
+      return hosts;
+    } finally {
+      r.unlock();
+    }
+  }
+
+  @Override
   public void deleteCluster(String clusterName)
       throws AmbariException {
     checkLoaded();
@@ -649,6 +684,7 @@ public class ClustersImpl implements Clusters {
       throws AmbariException {
     Host host = null;
     Cluster cluster = null;
+    HostEntity hostEntity = null;
 
     checkLoaded();
 
@@ -656,6 +692,7 @@ public class ClustersImpl implements Clusters {
     try {
       host = getHost(hostname);
       cluster = getCluster(clusterName);
+      hostEntity = hostDAO.findByName(hostname);
     } finally {
       r.unlock();
     }
@@ -677,7 +714,7 @@ public class ClustersImpl implements Clusters {
       host.refresh();
       cluster.refresh();
 
-      deleteConfigGroupHostMapping(hostname);
+      deleteConfigGroupHostMapping(hostEntity.getHostId());
 
       // Remove mapping of principals to the unmapped host
       kerberosPrincipalHostDAO.removeByHost(hostname);
@@ -699,11 +736,11 @@ public class ClustersImpl implements Clusters {
   }
 
   @Transactional
-  private void deleteConfigGroupHostMapping(String hostname) throws AmbariException {
+  private void deleteConfigGroupHostMapping(Long hostId) throws AmbariException {
     // Remove Config group mapping
     for (Cluster cluster : clusters.values()) {
       for (ConfigGroup configGroup : cluster.getConfigGroups().values()) {
-        configGroup.removeHost(hostname);
+        configGroup.removeHost(hostId);
       }
     }
   }
@@ -719,17 +756,23 @@ public class ClustersImpl implements Clusters {
     w.lock();
 
     try {
-      deleteConfigGroupHostMapping(hostname);
+      HostEntity entity = hostDAO.findByName(hostname);
+      
+      if (entity == null) {
+        return;
+      }
+
+      deleteConfigGroupHostMapping(entity.getHostId());
 
       Collection<HostVersionEntity> hostVersions = hosts.get(hostname).getAllHostVersions();
       for (HostVersionEntity hostVersion : hostVersions) {
         hostVersionDAO.remove(hostVersion);
       }
 
-      HostEntity entity = hostDAO.findByName(hostname);
       hostDAO.refresh(entity);
       hostDAO.remove(entity);
       hosts.remove(hostname);
+      hostsById.remove(entity.getHostId());
 
       // Remove mapping of principals to deleted host
       kerberosPrincipalHostDAO.removeByHost(hostname);
@@ -743,7 +786,6 @@ public class ClustersImpl implements Clusters {
     } finally {
       w.unlock();
     }
-
   }
 
   @Override

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroup.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroup.java b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroup.java
index a4cc6ac..4c806e5 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroup.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroup.java
@@ -84,7 +84,7 @@ public interface ConfigGroup {
    * List of hosts to which configs are applied
    * @return
    */
-  public Map<String, Host> getHosts();
+  public Map<Long, Host> getHosts();
 
   /**
    * List of @Config objects
@@ -137,7 +137,7 @@ public interface ConfigGroup {
    * Reassign the set of hosts associated with this config group
    * @param hosts
    */
-  public void setHosts(Map<String, Host> hosts);
+  public void setHosts(Map<Long, Host> hosts);
 
   /**
    * Reassign the set of configs associated with this config group
@@ -148,7 +148,7 @@ public interface ConfigGroup {
   /**
    * Remove host mapping
    */
-  public void removeHost(String hostname) throws AmbariException;
+  public void removeHost(Long hostId) throws AmbariException;
 
   String getServiceName();
 

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupFactory.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupFactory.java b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupFactory.java
index d4597af..9abadf3 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupFactory.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupFactory.java
@@ -32,7 +32,7 @@ public interface ConfigGroupFactory {
                        @Assisted("tag") String tag,
                        @Assisted("description") String description,
                        @Assisted("configs") Map<String, Config> configs,
-                       @Assisted("hosts") Map<String, Host> hosts);
+                       @Assisted("hosts") Map<Long, Host> hosts);
 
   ConfigGroup createExisting(Cluster cluster, ConfigGroupEntity entity);
 }

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java
index ffa085a..4c5d016 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/configgroup/ConfigGroupImpl.java
@@ -62,7 +62,7 @@ public class ConfigGroupImpl implements ConfigGroup {
 
   private Cluster cluster;
   private ConfigGroupEntity configGroupEntity;
-  private Map<String, Host> hosts;
+  private Map<Long, Host> hosts;
   private Map<String, Config> configurations;
   private volatile boolean isPersisted = false;
 
@@ -89,7 +89,7 @@ public class ConfigGroupImpl implements ConfigGroup {
                          @Assisted("tag") String tag,
                          @Assisted("description") String description,
                          @Assisted("configs") Map<String, Config> configs,
-                         @Assisted("hosts") Map<String, Host> hosts,
+                         @Assisted("hosts") Map<Long, Host> hosts,
                          Injector injector) {
     injector.injectMembers(this);
     this.cluster = cluster;
@@ -103,7 +103,7 @@ public class ConfigGroupImpl implements ConfigGroup {
     if (hosts != null) {
       this.hosts = hosts;
     } else {
-      this.hosts = new HashMap<String, Host>();
+      this.hosts = new HashMap<Long, Host>();
     }
 
     if (configs != null) {
@@ -122,7 +122,7 @@ public class ConfigGroupImpl implements ConfigGroup {
 
     this.configGroupEntity = configGroupEntity;
     configurations = new HashMap<String, Config>();
-    hosts = new HashMap<String, Host>();
+    hosts = new HashMap<Long, Host>();
 
     // Populate configs
     for (ConfigGroupConfigMappingEntity configMappingEntity : configGroupEntity
@@ -147,8 +147,9 @@ public class ConfigGroupImpl implements ConfigGroup {
 
       try {
         Host host = clusters.getHost(hostMappingEntity.getHostname());
-        if (host != null) {
-          hosts.put(host.getHostName(), host);
+        HostEntity hostEntity = hostMappingEntity.getHostEntity();
+        if (host != null && hostEntity != null) {
+          hosts.put(hostEntity.getHostId(), host);
         }
       } catch (AmbariException e) {
         String msg = "Host seems to be deleted but Config group mapping still " +
@@ -235,7 +236,7 @@ public class ConfigGroupImpl implements ConfigGroup {
   }
 
   @Override
-  public Map<String, Host> getHosts() {
+  public Map<Long, Host> getHosts() {
     readWriteLock.readLock().lock();
     try {
       return Collections.unmodifiableMap(hosts);
@@ -260,7 +261,7 @@ public class ConfigGroupImpl implements ConfigGroup {
    * @param hosts
    */
   @Override
-  public void setHosts(Map<String, Host> hosts) {
+  public void setHosts(Map<Long, Host> hosts) {
     readWriteLock.writeLock().lock();
     try {
       this.hosts = hosts;
@@ -287,23 +288,25 @@ public class ConfigGroupImpl implements ConfigGroup {
 
   @Override
   @Transactional
-  public void removeHost(String hostname) throws AmbariException {
+  public void removeHost(Long hostId) throws AmbariException {
     readWriteLock.writeLock().lock();
     try {
-      if (hosts.containsKey(hostname)) {
-        LOG.info("Removing host from config group, hostname = " + hostname);
-        hosts.remove(hostname);
+      if (hosts.containsKey(hostId)) {
+        String hostName = hosts.get(hostId).getHostName();
+        LOG.info("Removing host from config group, hostid = " + hostId + ", hostname = " + hostName);
+        hosts.remove(hostId);
         try {
           ConfigGroupHostMappingEntityPK hostMappingEntityPK = new
             ConfigGroupHostMappingEntityPK();
-          hostMappingEntityPK.setHostname(hostname);
+          hostMappingEntityPK.setHostId(hostId);
           hostMappingEntityPK.setConfigGroupId(configGroupEntity.getGroupId());
           configGroupHostMappingDAO.removeByPK(hostMappingEntityPK);
         } catch (Exception e) {
           LOG.error("Failed to delete config group host mapping"
             + ", clusterName = " + getClusterName()
             + ", id = " + getId()
-            + ", hostname = " + hostname, e);
+            + ", hostid = " + hostId
+            + ", hostname = " + hostName, e);
           throw new AmbariException(e.getMessage());
         }
       }
@@ -366,7 +369,7 @@ public class ConfigGroupImpl implements ConfigGroup {
         if (hostEntity != null) {
           ConfigGroupHostMappingEntity hostMappingEntity = new
             ConfigGroupHostMappingEntity();
-          hostMappingEntity.setHostname(host.getHostName());
+          hostMappingEntity.setHostId(hostEntity.getHostId());
           hostMappingEntity.setHostEntity(hostEntity);
           hostMappingEntity.setConfigGroupEntity(configGroupEntity);
           hostMappingEntity.setConfigGroupId(configGroupEntity.getGroupId());
@@ -487,7 +490,10 @@ public class ConfigGroupImpl implements ConfigGroup {
               configGroupEntity.getGroupName());
           }
         }
-        hosts.put(host.getHostName(), host);
+        HostEntity hostEntity = hostDAO.findByName(host.getHostName());
+        if (hostEntity != null) {
+          hosts.put(hostEntity.getHostId(), host);
+        }
       }
     } finally {
       readWriteLock.writeLock().unlock();

http://git-wip-us.apache.org/repos/asf/ambari/blob/290276c6/ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java
----------------------------------------------------------------------
diff --git a/ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java b/ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java
index 41cfee7..50d762e 100644
--- a/ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java
+++ b/ambari-server/src/main/java/org/apache/ambari/server/state/host/HostImpl.java
@@ -1069,6 +1069,29 @@ public class HostImpl implements Host {
   }
 
   @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+
+    Host that = (Host) o;
+
+    return this.getHostName().equals(that.getHostName());
+  }
+
+  @Override
+  public int hashCode() {
+    return (null == getHostName() ? 0 : getHostName().hashCode());
+  }
+
+  public int compareTo(HostEntity other) {
+    return getHostName().compareTo(other.getHostName());
+  }
+  
+  @Override
   public HostResponse convertToResponse() {
     try {
       readLock.lock();
@@ -1200,7 +1223,7 @@ public class HostImpl implements Host {
     try {
       // set all old mappings for this type to empty
       for (HostConfigMapping e : hostConfigMappingDAO.findByType(clusterId,
-          hostEntity.getHostName(), config.getType())) {
+          hostEntity.getHostId(), config.getType())) {
         e.setSelected(0);
         hostConfigMappingDAO.merge(e);
       }
@@ -1208,7 +1231,7 @@ public class HostImpl implements Host {
       HostConfigMapping hostConfigMapping = new HostConfigMappingImpl();
       hostConfigMapping.setClusterId(clusterId);
       hostConfigMapping.setCreateTimestamp(System.currentTimeMillis());
-      hostConfigMapping.setHostName(hostEntity.getHostName());
+      hostConfigMapping.setHostId(hostEntity.getHostId());
       hostConfigMapping.setSelected(1);
       hostConfigMapping.setUser(user);
       hostConfigMapping.setType(config.getType());
@@ -1230,7 +1253,7 @@ public class HostImpl implements Host {
     Map<String, DesiredConfig> map = new HashMap<String, DesiredConfig>();
 
     for (HostConfigMapping e : hostConfigMappingDAO.findSelected(
-        clusterId, hostEntity.getHostName())) {
+        clusterId, hostEntity.getHostId())) {
 
       DesiredConfig dc = new DesiredConfig();
       dc.setTag(e.getVersion());
@@ -1289,7 +1312,7 @@ public class HostImpl implements Host {
   }
 
   private HostConfigMapping getDesiredConfigEntity(long clusterId, String type) {
-    return hostConfigMappingDAO.findSelectedByType(clusterId, hostEntity.getHostName(), type);
+    return hostConfigMappingDAO.findSelectedByType(clusterId, hostEntity.getHostId(), type);
   }
 
   private void ensureMaintMap() {