Understanding MongoDB and Its Importance
MongoDB is a powerful, open-source NoSQL database that has gained immense popularity in the tech industry due to its scalability, flexibility, and performance. It stores data in flexible, JSON-like documents, which means fields can vary from document to document and data structure can be changed over time. This model allows for the storage of complex data types, making it an excellent choice for applications that require a non-relational database structure.
Prerequisites for Installing MongoDB on Ubuntu 20.04
Before diving into the installation process, it’s essential to ensure that your system meets the necessary requirements. Here are the prerequisites for installing MongoDB on Ubuntu 20.04:
- A machine running Ubuntu 20.04
- Access to a terminal window/command line (Ctrl-Alt-T)
- A user account with sudo privileges
- An internet connection to download the necessary packages
- Basic knowledge of Linux commands
Step-by-Step Guide to Installing MongoDB on Ubuntu 20.04
Step 1: Update the System Packages
Before installing any new software, it’s a good practice to update the system’s package list. This ensures that you have the latest versions of the packages and their dependencies. To update the package list, run the following command:
sudo apt update
Step 2: Import the MongoDB Repository GPG Key
MongoDB is not included in the default Ubuntu repositories. Therefore, you need to import the MongoDB repository GPG key to ensure the authenticity of the software you’re installing. Use the following command to import the GPG key:
wget -qO - https://www.mongodb.org/static/pgp/server-4.4.asc | sudo apt-key add -
Step 3: Add the MongoDB Repository
After importing the GPG key, the next step is to add the MongoDB repository to your system. This will allow you to install MongoDB directly using the apt package manager. Add the repository with the following command:
echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/4.4 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.4.list
Step 4: Install MongoDB Packages
With the repository added, you can now install MongoDB. First, update the package list to include the newly added repository, and then install the MongoDB package using the following commands:
sudo apt update
sudo apt install -y mongodb-org
Step 5: Start and Verify the MongoDB Service
Once the installation is complete, you need to start the MongoDB service. You can do this with the following command:
sudo systemctl start mongod
After starting the service, ensure that MongoDB is running by checking its status:
sudo systemctl status mongod
If MongoDB is running correctly, you should see an output indicating that the service is active.
Step 6: Enable MongoDB to Start on Boot
To ensure that MongoDB starts automatically when the system boots, enable it with the following command:
sudo systemctl enable mongod
Configuring MongoDB on Ubuntu 20.04
Basic Configuration
After installation, you might want to configure MongoDB to suit your specific needs. The main configuration file for MongoDB is located at /etc/mongod.conf. This file is written in YAML and can be edited to change settings such as the port number, storage engine, and security options.
Securing MongoDB
By default, MongoDB is not secured, and it’s crucial to enable authentication to prevent unauthorized access. To enable authentication, you need to create an administrative user and then modify the MongoDB configuration file to enforce authentication.
- Create an administrative user:
mongo
use admin
db.createUser({
user: "admin",
pwd: "your_password",
roles: [{ role: "userAdminAnyDatabase", db: "admin" }]
})
exit
sudo nano /etc/mongod.conf
In the configuration file, locate the security section and add the following lines:
security:
authorization: "enabled"
Save the file and restart the MongoDB service for the changes to take effect:
sudo systemctl restart mongod
Managing the MongoDB Service
Understanding how to manage the MongoDB service is essential for maintaining your database. Here are some common service management commands:
- To stop the MongoDB service:
sudo systemctl stop mongod
sudo systemctl restart mongod
sudo systemctl disable mongod
Connecting to MongoDB
Once MongoDB is installed and running, you can connect to it using the MongoDB shell. To enter the shell, simply type:
mongo
If you have enabled authentication, you will need to log in with the user credentials you created earlier:
mongo -u admin -p your_password --authenticationDatabase admin
Uninstalling MongoDB from Ubuntu 20.04
If you need to uninstall MongoDB from your system, you can do so by following these steps:
- Stop the MongoDB service:
sudo systemctl stop mongod
sudo apt purge mongodb-org*
sudo rm -r /var/log/mongodb
sudo rm -r /var/lib/mongodb
Troubleshooting Common MongoDB Installation Issues
During the installation and configuration process, you may encounter issues. Here are some common problems and their solutions:
- Failed to start mongod.service: This can happen if there are issues with the MongoDB configuration file or if the database files are corrupt. Check the MongoDB log files for more information.
- GPG key import failure: If you encounter an error while importing the GPG key, ensure that you have an internet connection and that the key server is accessible.
- Package installation errors: If apt fails to install the MongoDB packages, make sure that the repository was added correctly and that your system is updated.
Frequently Asked Questions
Can I install a specific version of MongoDB?
Yes, you can install a specific version of MongoDB by specifying the version number in the installation command. For example, to install MongoDB 4.4.6, you would use:
sudo apt install -y mongodb-org=4.4.6 mongodb-org-server=4.4.6 mongodb-org-shell=4.4.6 mongodb-org-mongos=4.4.6 mongodb-org-tools=4.4.6
How do I update MongoDB to the latest version?
To update MongoDB to the latest version, you can use the following commands:
sudo apt update
sudo apt upgrade
Is MongoDB free to use?
MongoDB offers both free and paid versions. The community edition is free to use, while the enterprise edition requires a subscription.
How do I back up my MongoDB database?
You can back up your MongoDB database using the mongodump command-line utility, which creates a binary export of the contents of a database.
How can I ensure high availability for my MongoDB database?
To ensure high availability, you can set up a MongoDB replica set, which is a group of mongod instances that maintain the same data set.
References
- MongoDB Official Documentation: https://docs.mongodb.com/manual/installation/
- Ubuntu Official Documentation: https://ubuntu.com/server/docs
- MongoDB Security Checklist: https://docs.mongodb.com/manual/administration/security-checklist/
