redis getaddrinfo ENOTFOUND - node.js,redis连接

嗨我试图从node.js连接redis成功,现在我在亚马逊ec2实例上托管我的node.js服务器应用程序和亚马逊弹性缓存实例上的redis连接到redis是成功的但偶尔我会得到下面提到的错误.

var pub = redis.createClient(6379,'quizredis.qnsdtp.0001.apse1.cache.amazonaws.com'); 


events.js:72
    throw er; // Unhandled 'error' event
          ^       Error: Redis connection to quizredis.qnsdtp.0001.apse1.cache.amazonaws.com:6379 failed - getaddrinfo ENOTFOUND
at RedisClient.on_error (/home/ec2-user/roomChat-7/node_modules/redis/index.js:196:24)
at Socket. (/home/ec2-user/roomChat-7/node_modules/redis/index.js:106:14)
at Socket.EventEmitter.emit (events.js:95:17)
at net.js:813:16

我使用redis-npm模块;