How to Resize MongoDB Database Clusters

Validated on 28 Jun 2021 • Last edited on 18 Dec 2024

MongoDB is a source-available cross-platform document-oriented database program for high-volume storage. Classified as a NoSQL database program, MongoDB uses JSON-like documents with optional schemas.

You can resize existing MongoDB database clusters at any time to add more CPUs, RAM, and storage. To avoid data loss, you cannot decrease the size of database clusters.

Resize a Database Cluster Using the CLI

Note

To resize a database cluster using doctl, you need to provide a value for the --size flag, which specifies the cluster’s new configuration (number of CPUs, amount of RAM, and hard disk space). Use the doctl databases options slugs command to get a list of available values.

You can also review a list of available slugs for each engine on its pricing page.

How to Resize a Database Cluster Using the DigitalOcean CLI

Install doctl, the DigitalOcean command-line tool.
Create a personal access token and save it for use with doctl.
Use the token to grant doctl access to your DigitalOcean account.
```
          doctl auth init
          
```

Finally, run doctl databases resize. Basic usage looks like this, but you can read the usage docs for more details:

            doctl databases resize <database-cluster-id> [flags]

The following example resizes a PostgreSQL or MySQL database to have two nodes, 16 vCPUs, 64 GB of memory, and 2048 GiB of storage space:

              doctl databases resize ca9f591d-9999-5555-a0ef-1c02d1d1e352 --num-nodes 2 --size db-s-16vcpu-64gb --storage-size-mib 2048000 --wait true

Resize a Database Cluster Using the API

Note

To resize a database cluster using the API, you need to provide a value for the size field, which specifies the cluster’s configuration (number of CPUs, amount of RAM, and hard disk space). Use the /v2/databases/options endpoint to get a list of available values.

You can also review a list of available slugs for each engine on its pricing page.

How to Resize a Database Cluster Using the DigitalOcean API

Create a personal access token and save it for use with the API.

Send a PUT request to https://api.digitalocean.com/v2/databases/{database_cluster_uuid}/resize

cURL

Using cURL:

                curl -X PUT \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \
-d '{"size":"db-s-4vcpu-8gb", "num_nodes":3, "storage_size_mib":163840}' \
"https://api.digitalocean.com/v2/databases/9cc10173-e9ea-4176-9dbc-a4cee4c4ff30/resize"

Go

Using Godo, the official DigitalOcean V2 API client for Go:

                import (
    "context"
    "github.com/digitalocean/godo"
)

func main() {
    pat := "mytoken"

    client := godo.NewFromToken(pat)
    ctx := context.TODO()

    resizeRequest := &godo.DatabaseResizeRequest{
        SizeSlug: "db-s-4vcpu-8gb",
        NumNodes: 3,
        StorageSizeMib: 163840,
    }
}

Python

                import os
from pydo import Client

client = Client(token=os.environ.get("DIGITALOCEAN_TOKEN"))

req = {
  "size": "db-s-4vcpu-8gb",
  "num_nodes": 3,
  "storage_size_mib": 163840
}

update_resp = client.databases.update_cluster_size(database_cluster_uuid="a7a8bas", body=req)

Resize a Database Cluster Using the Control Panel

To resize a MongoDB database cluster, click the name of the cluster in the control panel to go to its Overview page, then click the Settings tab.

You cannot reduce the amount of storage in a cluster below the amount of storage you are currently using in your cluster.

To switch to a database cluster plan with less storage, fork the cluster and select a smaller database cluster plan for the new cluster.

In the Cluster configuration section, click Edit. Select your cluster configuration and CPU option.

Cluster configuration section with additional nodes selected

You can also select your storage size.

Once you have selected your new configuration and size, click Save to provision the new configuration. The provisioning takes several minutes but the total time depends on the size of the cluster.

Your cluster’s state changes from Active to Resizing until the process is done. You can expect no downtime and do not need to take action.