code: private static Configuration enableClusteringHashGroups(String cacheName, Configuration configuration) {
  		if ( configuration.clustering().hash().groups().enabled() ) {
  			return configuration;
  		}
  		LOG.clusteringHashGroupsMustBeEnabled( cacheName );
  		ConfigurationBuilder builder = new ConfigurationBuilder().read( configuration );
  		builder.clustering().hash().groups().enabled();
  		return builder.build();
  	}
docs: Enable the clustering.hash.groups configuration if it's not already enabled.
  <p>
  Infinispan requires this option enabled because we are using fine grained maps.
  The function will log a warning if the property is disabled.
  
  @return the updated configuration