private Map<String, Map<String, String>> addAdditionalConfigurations(Cluster cluster, Map<String, Map<String, String>> configurations,
                                                                       String hostname, Map<String, String> kerberosDescriptorProperties,
                                                                       KerberosDescriptor userDescriptor)
          throws AmbariException {

    return addAdditionalConfigurations(cluster, configurations, hostname, kerberosDescriptorProperties,
            userDescriptor, null, null);
  }
Add configurations related to Kerberos, to a previously created map of configurations.
<p/>
The supplied map of configurations is expected to be mutable and will be altered.

@param cluster                      the cluster
@param configurations               a map of configurations
@param hostname                     a hostname
@param kerberosDescriptorProperties the Kerberos descriptor properties
@return the supplied map of configurations with updates applied
@throws AmbariException
ambari-server/src/main/java/org/apache/ambari/server/controller/KerberosHelperImpl.java