anchor.diff:      };
   
       logging = mkOption {
  -      description = "Elasticsearch logging configuration";
  +      description = "Elasticsearch logging configuration.";
         default = ''
           rootLogger: INFO, console
           logger:
  
positive.code:     };
  
      extraCmdLineOptions = mkOption {
        description = "Extra command line options for the elasticsearch launcher";
        default = [];
        type = types.listOf types.string;
        example = [ "-Djava.net.preferIPv4Stack=true" ];
  
negative.code: 
    options.services.elasticsearch = {
      enable = mkOption {
        description = "Whether to enable elasticsearch.";
        default = false;
        type = types.uniq types.bool;
      };
  
      host = mkOption {
        description = "Elasticsearch listen address.";
        default = "127.0.0.1";
        type = types.str;
      };
  
      port = mkOption {
        description = "Elasticsearch port to listen for HTTP traffic.";
        default = 9200;
        type = types.int;
      };
  
      tcp_port = mkOption {
        description = "Elasticsearch port for the node to node communication.";
        default = 9300;
        type = types.int;
      };
  
      cluster_name = mkOption {
        description = "Elasticsearch name that identifies your cluster for auto-discovery.";
        default = "elasticsearch";
        type = types.str;
      };
  
      extraConf = mkOption {
        description = "Extra configuration for elasticsearch.";
        default = "";
        type = types.str;
        example = ''
  