How to Backup MongoDB Database: Simple Steps and Examples

To backup a MongoDB database, use the mongodump command-line tool which creates a binary export of your data. Run mongodump --db yourDatabaseName --out /path/to/backup to save the backup files to a folder.

Syntax

The mongodump command exports the contents of a MongoDB database into BSON files. Key parts include:

• --db: specifies the database name to backup.
• --out: specifies the directory where backup files will be saved.
• --host: optional, specifies the MongoDB server address.
• --port: optional, specifies the server port.

bash

mongodump --db <database_name> --out <backup_directory>

Example

This example backs up the database named mydb to a folder called backup in the current directory.

bash

mongodump --db mydb --out ./backup

Output

2024-06-01T12:00:00.000+0000	writing mydb.collection1 to ./backup/mydb/collection1.bson
2024-06-01T12:00:00.100+0000	writing mydb.collection2 to ./backup/mydb/collection2.bson
Dump completed successfully.

Common Pitfalls

Common mistakes when backing up MongoDB include:

• Not specifying the --db option, which causes mongodump to backup all databases, possibly creating large files.
• Backing up while the database is heavily written to, which can cause inconsistent backups.
• Not having write permissions to the backup directory.

Always ensure you have enough disk space and consider stopping writes or using a replica set for consistent backups.

bash

mongodump --out ./backup
# This backs up all databases, which might be unintended.

mongodump --db mydb --out ./backup
# Correct: backs up only the 'mydb' database.

Quick Reference

Option	Description	Example
--db	Specify database name to backup	--db mydb
--out	Directory to save backup files	--out ./backup
--host	MongoDB server address	--host localhost
--port	MongoDB server port	--port 27017
--gzip	Compress backup files	--gzip

Key Takeaways

Use mongodump with --db and --out options to backup a specific MongoDB database.

Ensure you have write permissions and enough disk space for the backup folder.

Avoid backing up during heavy write operations to prevent inconsistent backups.

Use --gzip to compress backups and save storage space.

Backing up all databases without --db can create large files unintentionally.