Migrating MongoDB clusters

To migrate your MongoDB database to Yandex StoreDoc, you need to transfer the actual data, write-lock the old database, and transfer the load to the Yandex Cloud DB cluster.

Performing migration with Data Transfer allows you to:

• Migrate the database without interrupting user service.
• Migrate from older MongoDB versions to newer versions.
• Eliminate the need for an intermediate VM or public internet access to your Yandex StoreDoc target cluster.

For more information, see Problems addressed by Yandex Data Transfer.

To use this migration method, allow connecting to the source cluster from the internet.

Required paid resourcesRequired paid resources

The support cost for this solution includes:

• Yandex StoreDoc cluster fee: using computational resources allocated to hosts and disk storage (see Yandex StoreDoc pricing).
• Fee for public IP addresses if public access is enabled for cluster hosts (see Virtual Private Cloud pricing).
• Transfer fee: computing resource usage and number of transferred data rows (see Data Transfer pricing).

Getting startedGetting started

Create a Yandex StoreDoc target cluster with the computing capacity and storage size appropriate for the environment where the migrated database is deployed.

The source and target database names must be the same.

Transferring dataTransferring data

1. Prepare the source cluster.

2. Prepare the target cluster.

3. Create a source endpoint with the following parameters:

   • Database type: MongoDB.

   • Endpoint parameters → Connection settings: Custom installation.

     Configure the source cluster connection settings.

   Note

   Transferring of Time Series collections is not supported, so you should exclude such collections in the endpoint settings.

4. Create a target endpoint with the following parameters:

   • Database type: MongoDB.

   • Endpoint parameters → Connection settings: Yandex StoreDoc cluster.

     Specify the ID of the target cluster.

5. Create a Snapshot and increment-type transfer and configure it to use the previously created endpoints.

   To make large collections (over 1 GB) copy more quickly, enable parallel copy in the transfer settings. Specify two or more workers. The collection will be split into the specified number of parts that will be copied concurrently.

   For parallel copy to work, the _id field data type must be the same for all documents in the same collection. If a transfer discovers a type mismatch, the collection will not be partitioned but transferred in a single thread instead. If needed, remove documents with mismatched data types from the collection before starting a transfer.

   Note

   If a document with a different data type is added to a collection after a transfer starts, the transfer will move it at the replication stage after the parallel copy operation is completed. However, when re-activated, the transfer will not be able to partition a collection because the _id field type requirement will not be met for some of the documents in the collection.

6. Activate the transfer.

7. Wait for the transfer status to change to Replicating.

8. Switch the source cluster to "read-only" mode and transfer the load to the target cluster.

9. On the transfer monitoring page, wait for the Maximum data transfer delay metric to decrease to zero. This means that all changes that occurred in the source cluster after data copying was completed are transferred to the target cluster.

10. Deactivate the transfer and wait for its status to change to Stopped.

    For more information about transfer statuses, see Transfer lifecycle.

11. Delete the stopped transfer.

12. Delete the source and target endpoints.

See alsoSee also

For other migration methods, see this Yandex StoreDoc tutorial.