Installing MongoDB

Source

Introduction

MongoDB is a free and open-source NoSQL document database used commonly in modern web applications. This tutorial will help you set up MongoDB on your server for a production application environment.
As of publication time, the official Ubuntu 16.04 MongoDB packages have not yet been updated to use the new systemd init system which is enabled by default on Ubuntu 16.04. Running MongoDB using those packages on a clean Ubuntu 16.04 server involves following an additional step to configure MongoDB as a systemd service that will automatically start on boot.

Prerequisites

To follow this tutorial, you will need:

• One Ubuntu 16.04 server set up by following this initial server setup tutorial, including a sudo non-root user

Step 1 — Adding the MongoDB Repository

MongoDB is already included in Ubuntu package repositories, but the official MongoDB repository provides most up-to-date version and is the recommended way of installing the software. In this step, we will add this official repository to our server.
Ubuntu ensures the authenticity of software packages by verifying that they are signed with GPG keys, so we first have to import they key for the official MongoDB repository.

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv EA312927

After successfully importing the key, you will see:

Output

gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)

Next, we have to add the MongoDB repository details so apt will know where to download the packages from.
Issue the following command to create a list file for MongoDB.

echo "deb http://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.2.list

After adding the repository details, we need to update the packages list.

sudo apt-get update

Step 2 — Installing and Verifying MongoDB

Now we can install the MongoDB package itself.

sudo apt-get install -y mongodb-org

This command will install several packages containing latest stable version of MongoDB along with helpful management tools for the MongoDB server.
In order to properly launch MongoDB as a service on Ubuntu 16.04, we additionally need to create a unit file describing the service. A unit file tells systemd how to manage a resource. The most common unit type is a service, which determines how to start or stop the service, when should it be automatically started at boot, and whether it is dependent on other software to run.
We'll create a unit file to manage the MongoDB service. Create a configuration file named mongodb.service in the /etc/systemd/system directory using nano or your favorite text editor.

sudo nano /etc/systemd/system/mongodb.service

Paste in the following contents, then save and close the file.

/etc/systemd/system/mongodb.service

[Unit]
Description=High-performance, schema-free document-oriented database
After=network.target

[Service]
User=mongodb
ExecStart=/usr/bin/mongod --quiet --config /etc/mongod.conf

[Install]
WantedBy=multi-user.target

This file has a simple structure:

• The Unit section contains the overview (e.g. a human-readable description for MongoDB service) as well as dependencies that must be satisfied before the service is started. In our case, MongoDB depends on networking already being available, hence network.target here.
• The Service section how the service should be started. The User directive specifies that the server will be run under the mongodb user, and the ExecStart directive defines the startup command for MongoDB server.
• The last section, Install, tells systemd when the service should be automatically started. The multi-user.target is a standard system startup sequence, which means the server will be automatically started during boot.

Next, start the newly created service with systemctl.

sudo systemctl start mongodb

While there is no output to this command, you can also use systemctl to check that the service has started properly.

sudo systemctl status mongodb

Output

● mongodb.service - High-performance, schema-free document-oriented database
   Loaded: loaded (/etc/systemd/system/mongodb.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2016-04-25 14:57:20 EDT; 1min 30s ago
 Main PID: 4093 (mongod)
    Tasks: 16 (limit: 512)
   Memory: 47.1M
      CPU: 1.224s
   CGroup: /system.slice/mongodb.service
           └─4093 /usr/bin/mongod --quiet --config /etc/mongod.conf

The last step is to enable automatically starting MongoDB when the system starts.

sudo systemctl enable mongodb

The MongoDB server now configured and running, and you can manage the MongoDB service using the systemctl command (e.g. sudo systemctl mongodb stop, sudo systemctl mongodb start).