public String getHostsMapFile() {
    LOG.info("Hosts Mapping File " + getProperty(SRVR_HOSTS_MAPPING));
    return getProperty(SRVR_HOSTS_MAPPING);
  }
Get the file that will be used for host mapping.
@return null if such a file is not present, value if present.
ambari-server/src/main/java/org/apache/ambari/server/configuration/Configuration.java