我只是和mongo shell玩，结果得到了Cannot use commands write mode, degrading to compatibility mode分.
我连接到远程mongo服务器(mongolab)，并试图通过我的简单脚本将新记录插入到集合中:
// script.js
db = connect(host + ":" + port +"/" + dbName);
db.auth(username, password);
db.test2.insert({ item: "card", qty: 15 });
我以mongo script.js的速度运行脚本，得到:
MongoDB shell version: 2.6.3
connecting to: test
connecting to: my.mongolab.com:port/DBname
Cannot use commands write mode, degrading to compatibility mode
怎么了？此外，当我通过mongo my.mongolab.com:port/DBname -u <dbuser> -p <dbpassword>连接后执行类似的查询时，一切都正常.