Seed with `mongorestore`

You can use mongodump and mongorestore to seed MongoDB Atlas cluster with data from an existing MongoDB standalone or replica set. For guidance on seeding data from an existing MongoDB sharded cluster, contact Atlas support by clicking Support in the left-hand navigation of the Atlas user interface.

While you can scale an M0 Free Tier cluster to an M10+ paid cluster using the Atlas user interface, you can also use mongodump and mongorestore procedures in this section to copy data from an M0 Free Tier cluster to an M10+ cluster.

Considerations

Recommended `mongodump` and `mongorestore` Version

Use the latest stable release version of mongodump and mongorestore for this procedure.

Downtime Required

To ensure an up-to-date migration, schedule a maintenance window where you can stop all writes to your source cluster. Any write operations issued to the source cluster after the mongodump portion of the procedure completes are not migrated to the target cluster.

You must cut-over your applications to the target Atlas cluster after mongorestore completes the data restoration before resuming write operations. See Connect to a Database Deployment for complete documentation on connecting to a Atlas cluster.

The total amount of downtime required depends on factors such as the size of data being migrated and the network connection between your source cluster and Atlas. If you have questions or concerns about extended downtime, contact Atlas support by clicking Support from the left-hand navigation of the Atlas UI.

For a guided minimal-downtime migration procedure, see Replica Set Live Migration or Sharded Cluster Live Migration.

Cluster Security

Atlas fully manages database user creation. If the source cluster enforces authentication:

Allow read access to the primary.
If you want to use mongorestore with the --oplogReplay option, you must delete both the admin``and the ``config directories from the dump directory that mongodump creates. Both the admin and the config directories contain database user information that you can't add to a Atlas cluster with mongorestore. Use the mongorestore --nsExclude to exclude the admin.system.* namespace.

You can't migrate any existing user or role information to Atlas. For the target Atlas cluster, create the appropriate database users for supporting your application's usage patterns. Update your applications as part of the cut-over procedure to use the new database users. To learn more, see Configure Database Users.

Performance

This procedure requires running mongodump and mongorestore on a host in the source cluster. These programs use system resources such as CPU and memory, and may impact the performance of the host.

Run this procedure during non-peak system usage, or during a scheduled maintenance window. If the source is a replica set, you can run this procedure from the host of a secondary member. After stopping writes to the cluster, allow the secondary to catch up to the primary before starting this procedure.

Pipe Behavior

This procedure uses linux pipes to stream the output of mongodump to mongorestore. If the mongorestore process can't keep up with the mongodump process, you may see broken pipe errors.

For guidance on addressing persistent broken pipe errors, contact Atlas support by clicking Support from the left-hand navigation of the Atlas user interface.

Procedure

The following tutorial uses mongodump and mongorestore to upload data from an existing MongoDB cluster to an Atlas cluster:

Optional: Create a database user in the source replica set.

Important

Optional

If your source cluster doesn't enforce authentication, skip this step.

If the source deployment enforces authentication, you must provide a database user with privileges to read any database as part of this procedure. To learn more about database user privileges, see MongoDB Role-Based Access Control.

If no such user exists, create a user in your source MongoDB replica set with the backup role on the admin database.

Example

Run the following command in mongosh to create the mySourceUser on the admin database and assign it the backup role. For replica sets, you must run this command against the primary.

use admin
db.createUser(
  {
     user: "<mySourceUser>",
     pwd: "<mySourcePassword>",
     roles: [ "backup" ]
  }
)

Assemble the `mongodump` command.

Based on the type of connection string you use, copy one of the following templates to into your preferred text editor:

Note

To connect to Atlas clusters, we recommend you connect with a DNS seed list connection string using the --uri option.

Note

If your password contains special characters, it must be percent-encoded.

Do not run this command yet. Proceed to the next step once you have modified the template.

Set up database user in the target Atlas cluster.

To run mongorestore against an Atlas cluster, you must specify a database user in the Atlas cluster that has the Atlas admin role.

If no such user exists, create the user:

If it is not already displayed, select your desired organization from the Organizations menu in the navigation bar.
Click Access Manager in the sidebar, or click Access Manager in the navigation bar, then click your organization.
Click Add New Database User.
Add an Atlas admin user.

To learn more about user management, see Configure Database Users.

Navigate to the Database Deployments page for your project.

If it is not already displayed, select the organization that contains your desired project from the Organizations menu in the navigation bar.
If it is not already displayed, select your desired project from the Projects menu in the navigation bar.
If the Database Deployments page is not already displayed, click Databases in the sidebar.

Choose Command Line Tools for your desired cluster.

From the menu for the cluster, click Command Line Tools.

Retrieve and modify the `mongorestore` connection template.

The Binary Import and Export Tools section of the Command Line Tools tab displays a copyable template with the minimum required options for connecting mongorestore to your Atlas cluster.

The template includes placeholder values for certain options. Copy and paste the template into your preferred text editor and make the following modifications:

password: replace this with the password for the user specified in username. The template includes a database user for the project as the username. If you want to authenticate as a different user, replace the value of username and specify the password for that user in password.
Add --nsExclude and set its value to "admin.system.*".
Add --archive.

Based on the type of connection string you use, your template should resemble one of the following commands:

Run `mongodump` and `mongorestore`.