public void mergeWithParent(Host parentHost) {
    if(null == parentHost) {
      return;
    }
    if(null == httpProperty && null != parentHost.getHttpProperty()) {
      httpProperty = parentHost.getHttpProperty();
    }
    if(null == httpsProperty && null != parentHost.getHttpsProperty()) {
      httpsProperty = parentHost.getHttpsProperty();
    }
    if(null == site && null != parentHost.getSite()) {
      site = parentHost.getSite();
    }
  }
The config type where the overridden host name comes from
ambari-server/src/main/java/org/apache/ambari/server/state/quicklinks/Host.java