Enable secure cluster connectivity

  • Article

This article explains how to use secure cluster connectivity for Azure Databricks workspaces. Secure cluster connectivity is also known as no public IP (NPIP). Although the serverless compute plane does not use secure cluster connectivity, serverless compute resources do not have public IP addresses.

Secure cluster connectivity overview

When secure cluster connectivity is enabled, customer virtual networks have no open ports and compute resources in the classic compute plane have no public IP addresses.

  • Each cluster initiates a connection to the control plane secure cluster connectivity relay during cluster creation. The cluster establishes this connection using port 443 (HTTPS) and uses a different IP address than is used for the web application and REST API.
  • When the control plane performs cluster administration tasks, these requests are sent to the cluster through this tunnel.

Note

All Azure Databricks network traffic between the classic compute plane VNet and the Azure Databricks control plane goes across the Microsoft network backbone, not the public internet. This is true even if secure cluster connectivity is disabled.

You can enable secure cluster connectivity on a new workspace or add it to an existing workspace that already uses VNet injection.

Enable secure cluster connectivity on a new workspace

You can enable secure cluster connectivity when you create a workspace using the Azure portal or an Azure Resource Manager (ARM) template.

Add secure cluster connectivity to an existing workspace

You can enable secure cluster connectivity on an existing workspace using the Azure portal, an ARM template, or azurerm Terraform provider version 3.41.0+. The upgrade requires that the workspace uses VNet injection.

Important

If you use a firewall or other network configuration changes to control ingress or egress from the classic compute plane, you might need to update your firewall or network security group rules at the same time as these changes for them to fully take effect. For example, using secure cluster connectivity, there is an additional outgoing connection to the control plane, and the incoming connections from the control plane are no longer used.

Step 1: Stop all compute resources

Stop all classic compute resources such as clusters, pools, or classic SQL warehouses. Databricks recommends planning the timing of the upgrade for down time.

Step 2: Update the workspace

You can update the workspace using the Azure portal, an ARM template, or Terraform.

Use Azure portal

  1. Go to your Azure Databricks workspace in the Azure portal.
  2. In the left navigation under Settings, click Networking.
  3. In the Network access tab, set Deploy Azure Databricks workspace with Secure Cluster Connectivity (No Public IP) to Enabled.
  4. Click Save.

The network update might take over 15 minutes to complete.

Apply an updated ARM template using Azure portal

Use an ARM template to set the enableNoPublicIp parameter to True (true).

Note

If your managed resource group has a custom name, you must modify the template accordingly. Contact your Azure Databricks account team for more information.

  1. Copy the following upgrade ARM template JSON:

      {
    "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "parameters": {
        "location": {
            "defaultValue": "[resourceGroup().location]",
            "type": "String",
            "metadata": {
                "description": "Location for all resources."
            }
        },
        "workspaceName": {
            "type": "String",
            "metadata": {
                "description": "The name of the Azure Databricks workspace to create."
            }
        },
        "apiVersion": {
            "defaultValue": "2023-02-01",
            "allowedValues": [
              "2018-04-01",
              "2020-02-15",
              "2022-04-01-preview",
              "2023-02-01"
            ],
            "type": "String",
            "metadata": {
                "description": "2018-03-15 for 'full region isolation control plane' and 2020-02-15 for 'FedRAMP certified' regions"
            }
        },
        "enableNoPublicIp": {
            "defaultValue": true,
            "type": "Bool"
        },
        "pricingTier": {
            "defaultValue": "premium",
            "allowedValues": [
                "premium",
                "standard",
                "trial"
            ],
            "type": "String",
            "metadata": {
                "description": "The pricing tier of workspace."
            }
        },
        "publicNetworkAccess": {
          "type": "string",
          "defaultValue": "Enabled",
          "allowedValues": [
            "Enabled",
            "Disabled"
          ],
          "metadata": {
            "description": "Indicates whether public network access is allowed to the workspace - possible values are Enabled or Disabled."
          }
        },
        "requiredNsgRules": {
          "type": "string",
          "defaultValue": "AllRules",
          "allowedValues": [
            "AllRules",
            "NoAzureDatabricksRules"
          ],
          "metadata": {
            "description": "Indicates whether to retain or remove the AzureDatabricks outbound NSG rule - possible values are AllRules or NoAzureDatabricksRules."
          }
        }
    },
    "variables": {
        "managedResourceGroupName": "[concat('databricks-rg-', parameters('workspaceName'), '-', uniqueString(parameters('workspaceName'), resourceGroup().id))]",
        "managedResourceGroupId": "[subscriptionResourceId('Microsoft.Resources/resourceGroups', variables('managedResourceGroupName'))]"
    },
    "resources": [
        {
            "type": "Microsoft.Databricks/workspaces",
            "apiVersion": "[parameters('apiVersion')]",
            "name": "[parameters('workspaceName')]",
            "location": "[parameters('location')]",
            "sku": {
                "name": "[parameters('pricingTier')]"
            },
            "properties": {
                "ManagedResourceGroupId": "[variables('managedResourceGroupId')]",
                "publicNetworkAccess": "[parameters('publicNetworkAccess')]",
                "requiredNsgRules": "[parameters('requiredNsgRules')]",
                "parameters": {
                    "enableNoPublicIp": {
                        "value": "[parameters('enableNoPublicIp')]"
                    }
                }
            }
        }
    ]
}

    1. Go to the Azure portal Custom deployment page.

    2. Click Build your own template in the editor.

    3. Paste in the JSON for the template that you copied.

    4. Click Save.

    5. Fill in the parameters.

    6. To update an existing workspace, use the same parameters that you used to create the workspace other than enableNoPublicIp which you must set to true. Set the subscription, region, workspace name, subnet names, resource ID of the existing VNet.

      Important

      The resource group name, workspace name, and subnet names are identical to your existing workspace so that this command updates the existing workspace rather than creating a new workspace.

    7. Click Review + Create.

    8. If there are no validation issues, click Create.

    The network update might take over 15 minutes to complete.

Apply an update using Terraform

For workspaces created with Terraform, you can update the workspace without recreating the workspace.

Important

You must use terraform-provider-azurerm version 3.41.0 or later, so upgrade your Terraform provider version as needed. Earlier versions attempt to recreate the workspace if you change any of these settings.

Change the following workspace settings:

  • no_public_ip in the custom_parameters block can be changed from false to true.

The network update might take over 15 minutes to complete.

Step 3: Validate the update

Once the workspace is in active state, the update job is completed. Verify that the update was applied:

  1. Open Azure Databricks in your web browser.

  2. Start one of the workspace's clusters and wait until the cluster is fully started.

  3. Go to your workspace instance in the Azure portal.

  4. Click the blue ID next to the field label Managed Resource Group.

  5. In that group, find the VMs for the cluster and click on one of them.

  6. In the VM settings, within Properties, look for the fields in the Networking area.

  7. Confirm that the Public IP address field is empty.

    If it's populated, the VM has a public IP address, which means the update failed.

Temporary rollback of upgrading to secure cluster connectivity

If something goes wrong during deployment you can reverse the process as a temporary rollback, but disabling SCC on a workspace is not supported other than for temporary rollback before continuing the upgrade later. If this is necessary temporarily, you can follow the instructions above for upgrade but set enableNoPublicIp to false instead of true.

Egress from workspace subnets

When you enable secure cluster connectivity, both of your workspace subnets are private subnets, since cluster nodes do not have public IP addresses.

The implementation details of network egress vary based on whether you use the default (managed) VNet or whether you use the VNet injection to provide your own VNet in which to deploy your workspace.

Important

Additional costs may be incurred due to increased egress traffic when you use secure cluster connectivity. For the most secure deployment, Azure and Databricks strongly recommend that you enable secure cluster connectivity.

Egress with default (managed) VNet

If you use secure cluster connectivity with the default VNet that Azure Databricks creates, Azure Databricks automatically creates a NAT gateway for outbound traffic from your workspace's subnets to the Azure backbone and public network. The NAT gateway is created within the managed resource group managed by Azure Databricks. You cannot modify this resource group or any resources provisioned within it. This NAT gateway incurs additional cost.

Egress with VNet injection

If you enable secure cluster connectivity on your workspace that uses VNet injection, Databricks recommends that your workspace has a stable egress public IP. Stable egress public IP addresses are useful because you can add them to external allow lists. For example, to connect from Azure Databricks to Salesforce with a stable outgoing IP address.

Warning

Azure announced that on September 30, 2025, default outbound access connectivity for virtual machines in Azure will be retired. See this announcement. This means that existing Azure Databricks workspaces that use default outbound access rather than a stable egress public IP might not continue to work after that date. Databricks recommends that you add explicit outbound methods for your workspaces before that date.

To add explicit outbound methods for you workspace, use an Azure NAT gateway or user-defined routes (UDRs).

  • Azure NAT gateway: Use an Azure NAT gateway if your deployments only need some customization. Configure the gateway on both of the workspace's subnets to ensure that all outbound traffic to the Azure backbone and public network transits through it. Clusters have a stable egress public IP, and you can modify the configuration for custom egress needs. You can configure this using either an Azure template or from the Azure portal.
  • UDRs: Use UDRs if your deployments require complex routing requirements or your workspaces use VNet injection with an egress firewall. UDRs ensure that network traffic is routed correctly for your workspace, either directly to the required endpoints or through an egress firewall. To use UDRs, you must add direct routes or allowed firewall rules for the Azure Databricks secure cluster connectivity relay and other required endpoints listed at User-defined route settings for Azure Databricks.

Warning

Do not use an egress load balancer with a workspace that has secure cluster connectivity enabled. In production systems, an egress load balancer can lead to risk of exhausting ports.