For version 3.0.

Install

On VPS (ip: 123.56.18.18), download MongoDB binary package for Ubuntu 14.04 and extract:

wget https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1404-3.0.3.tgz
cd /opt
tar zxf ~/mongodb-linux-x86_64-ubuntu1404-3.0.3.tgz
mkdir -p /data/db

Authentication Management

Start mongod without auth on VPS (ip: 123.56.18.18): mongod;

Connect to server with mongo 123.56.18.18; Create system user administrator:

use admin
db.createUser(
    {
      user: "superuser",
      pwd: "12345678",
      roles: [ "root" ]
    }
)

Create user in current database:

use products
db.createUser({user: "dba", pwd: "dba", roles: ["readWrite"]})
show users

Verify with db.getUsers().

Create a production config file mongo.conf:

net:
  #bindIp: 10.251.212.248
  port: 15515
systemLog:
  destination: file
  path: "mongo.log"
  logAppend: true
security:
  authorization: enabled

Stop and restart mongod with nohup mongod --config mongo.conf &;

Connect to server as a database user: mongo 123.56.18.18:15515/products -u niufair -p nfsecret. You can show collections, db.doc.insert(), etc.

Start Meteor app with MONGO_URL="mongodb://niufair:nfsecret@123.56.18.18:15515/products" meteor.

Connect to server as administrator: mongo 123.56.18.18:15515/admin -u leo -p leoisadmin.

Use db.getUsers() (or show users) and db.dropUser("username") to list and remove the user.

Create a new database under authentication

Say we want to create a new database named "bakdb":

mongo 123.56.18.18:15515/admin -u leo -p leoisadmin
use bakdb
db.createUser({user: "niufair", pwd: "nfsecret", roles: ["readWrite"]})

Verify: mongo -u niufair -p nfsecret 123.56.18.18:15515/bakdb;

Ref:

Enable Authentication after Creating the User Administrator

Add a User to a Database

Create an Administrative User with Unrestricted Access

Enable Client Access Control

Built-In Roles

http://stackoverflow.com/questions/4881208/how-to-put-username-password-in-mongodb

MMS

Connect mongodb server without authentication: mongo <ip>:<port>;