Automatically Backup Mongodb Databases Using Bash Scripting

MongoDB is a popular non-relationship database management system that stores keys and their values in a collection of documents rather than tables with fixed schemas. MongoDB supports a wide variety of options for horizontal scaling, making it an ideal tool for large enterprise production environments.

Backing up the data stored in a MongoDB database is an important step to maintain data integrity and disaster recovery plans. To assure that the MongoDB databases are backed up regularly to an external source such as a Linode Object Storage bucket, a simple Bash script can be created. Then, the Bash script can be configured to run daily using the Linux Cron job workflow.

Before You Begin

1. Learn about the fundamentals of Linode Object Storage by viewing the Get Started with Object Storage guide or by reviewing the available Object Storage guides.

2. Create a Linode Object Storage bucket. This bucket is used to store your MongoDB backups.

3. Create a pair of Access Keys for your Linode Object Storage bucket.

4. Install MongoDB on your Linux system.

Install Cyberduck CLI

In this guide, we use the Cyberduck CLI for interacting with your Linode Object Storage bucket. Cyberduck CLI, also referred to as duck, is a command line interface tool that allows you to access, and manage objects stored in your Linode bucket. We use duck for uploading our MongoDB backup files to our Linode bucket.

If you are using a Debian Linux distribution, install duck with the following commands:

echo -e "deb https://s3.amazonaws.com/repo.deb.cyberduck.io stable main" | sudo tee /etc/apt/sources.list.d/cyberduck.list > /dev/null
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys FE7097963FEFBE72
sudo apt-get update
sudo apt-get install duck

If you are using a Red Hat Linux distribution, install duck with the following commands:

echo -e "[duck-stable]\nname=duck-stable\nbaseurl=https://repo.cyberduck.io/stable/\$basearch/\nenabled=1\ngpgcheck=0" | sudo tee /etc/yum.repos.d/duck-stable.repo
sudo yum install duck

Create Bash Script

Navigate into your user’s home directory or your desired working directory. This guide uses the /home/linode-user directory for example purposes. Create a new file called backup_mongodb.sh using the following command:

touch backup_mongodb.sh

Open the above file in the nano text editor and add the following lines of code. For more information on Linux nano, check out the official nano documentation.

File: backup_mongodb.sh

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#!/bin/bash ### Variables in this section will need to be edited to reflect your configuration. ###### Start of section # Your Linux user's home directory export HOME=/home/linode-user # Your MongoDB's server hostname HOST=localhost # The MongoDB database to be backed up DBNAME=LINODE_DATABASE # Linode Object Storage bucket name. Replace this value with the name of your Linode bucket and it's associated region. This should be in the format {BUCKET_NAME}.{BUCKET_REGION}.linodeobjects.com BUCKET=mongodb-backups.us-southeast-1.linodeobjects.com # Linux user account USER=linode-user # Linode Bucket Access Key. You can use an environment variable to store your Linode Access Key, or you can store it in plain text in this script in the line below. Plain text is not recommended for production environments. LINODE_ACCESS_KEY=$LINODEACCESSKEY ###### End of section # Current time and date TIME=`/bin/date +%d-%m-%Y-%T` # Directory you'd like the MongoDB backup file to be saved to DEST=/home/$USER/tmp # Command to create a .tar file of the MongoDB backup files TAR=$DEST/$TIME.tar # Command to create the backup directory (-p to avoid warning if the directory already exists) /bin/mkdir -p $DEST # Echo for logging purposes echo "Backing up $HOST/$DBNAME to Linode $BUCKET on $TIME"; # Command to run the mongodump command that dumps all data for the specified database to the backup directory /usr/bin/mongodump -h $HOST -d $DBNAME -o $DEST # Create the .tar file of backup directory /bin/tar cvf $TAR -C $DEST . # Upload the .tar to Linode duck --username $LINODE_ACCESS_KEY --upload s3://$BUCKET/ $TAR # Log the end of the script echo "Backup of MongoDB databases to Linode bucket $BUCKET completed successfully."

Refer to the comments in the code to learn what each line in the code does.

Run the Bash Script

Before setting the above script to run automatically, execute the script to configure your Linode bucket’s access key pair. You need to set the appropriate permissions for this script to be executed. For more information on Linux file permissions, review our guide on Modifying File Permissions with chmod.

Modify the script’s permissions, then execute the script with the following commands:

chmod 755 backup_mongodb.sh
./backup_mongodb.sh

Enter your Linode Access keys as prompted, and choose the option to save them.

Schedule Backups as a Cron Job

Open the Cron task scheduler with the following command:

crontab -e

Select your preferred text editor from the menu and enter the following line in your Cron job file:

0 9 * * * /path/to/backup_mongodb.sh

Replace /path/to/ from the above line with the full directory path to your backup_mongodb.sh file.

The above Cron job is scheduled to run daily at 9:00 AM in your system’s configured time zone. For more information on Cron job configuration parameters, review our guide on Using Cron to Schedule Tasks for Certain Times or Intervals.

More Information

You may wish to consult the following resources for additional information on this topic. While these are provided in the hope that they will be useful, please note that we cannot vouch for the accuracy or timeliness of externally hosted materials.

• MongoDB
• Crontab
• Nano