rs-init.js

rsconf = {
           _id: "rs0",
           members: [
                      {
                       _id: 0,
                       host: "127.0.0.1:27017"
                      },
                      {
                       _id: 1,
                       host: "127.0.0.1:37017"
                      },
                      {
                       _id: 2,
                       host: "127.0.0.1:47017",
  	      arbiterOnly: true
                      }
                    ]
         }

rs.initiate(rsconf);
rs.status();