mongo error

mongo error

> node index.js

ec2-54-234-201-7.compute-1.amazonaws.com :27017
Error: No valid replicaset instance servers found
    at /var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/repl_set/repl_set.js:446:45
    at null.<anonymous> (/var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/server.js:499:7)
    at EventEmitter.emit (events.js:95:17)
    at null.<anonymous> (/var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:178:15)
    at EventEmitter.emit (events.js:98:17)
    at Socket.<anonymous> (/var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/connection.js:501:10)
    at Socket.EventEmitter.emit (events.js:92:17)
    at Socket._onTimeout (net.js:326:8)
    at Timer.unrefTimeout [as ontimeout] (timers.js:412:13)
    
Error: in process of connection
    at ReplSet.connect (/var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/repl_set/repl_set.js:167:21)
    at Db.open (/var/app/current/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/db.js:279:23)
    at SkinClass.SkinDb._open (/var/app/current/node_modules/mongoskin/lib/db.js:33:18)
    at SkinClass.open (/var/app/current/node_modules/mongoskin/lib/utils.js:162:14)
    at SkinClass.SkinCollection._open (/var/app/current/node_modules/mongoskin/lib/collection.js:49:17)
    at SkinClass.open (/var/app/current/node_modules/mongoskin/lib/utils.js:162:14)
    at SkinClass.SkinCursor._open (/var/app/current/node_modules/mongoskin/lib/cursor.js:28:25)
    at SkinClass.open (/var/app/current/node_modules/mongoskin/lib/utils.js:162:14)
    at SkinClass.(anonymous function) [as toArray] (/var/app/current/node_modules/mongoskin/lib/utils.js:116:14)
    at Object.getBatchFrom_id