The only supported method for adding disks to a Cloud Volumes ONTAP (CVO) aggregate is by using NetApp BlueXP. BlueXP is the orchestration and management plane for CVO instances. When an administrator initiates the "Add Capacity" action in BlueXP for an aggregate, BlueXP automatically handles the entire end-to-end workflow. This includes provisioning the necessary managed disks in the Azure cloud, attaching them to the CVO virtual machine instance, and then instructing the ONTAP software to incorporate these new disks into the specified aggregate. This process ensures that the cloud resource layer and the ONTAP configuration remain synchronized and fully supported by NetApp.

B. Assign more disks to the CVO VM in Azure Portal

This action bypasses the BlueXP management plane. While it attaches disks at the VM level, BlueXP and ONTAP are not correctly updated, leading to configuration drift and an unsupported state.

C. Add more disks in ONTAP System Manager

ONTAP System Manager can only manage disks that are already provisioned and attached to the CVO instance. It has no capability to provision the underlying Azure managed disks, making this an incomplete and unsupported method.

D. Use the "aggr add-disk" command on CLI

Similar to System Manager, the ONTAP command-line interface (CLI) cannot provision cloud resources. It can only add disks to an aggregate after they have been attached to the VM, which must be done via the supported BlueXP workflow.

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1. NetApp BlueXP Documentation, "Add disks to aggregates": This official documentation outlines the procedure for adding capacity. It states, "You can add capacity to an aggregate at any time from BlueXP. BlueXP adds disks to the aggregate and then resizes the volumes in the aggregate so they can use the new capacity." The entire procedure described is performed within the BlueXP user interface.

Source: NetApp BlueXP Documentation, docs.netapp.com/us-en/bluexp-cloud-volumes-ontap/task-add-disks-to-aggregates.html

2. NetApp Technical Report TR-4597, "Cloud Volumes ONTAP for Microsoft Azure Architectural Design and Implementation Guide": This report emphasizes the role of BlueXP as the central management tool.

Section: "Managing Cloud Volumes ONTAP" states, "NetApp BlueXP is the single management interface that you can use to deploy and manage Cloud Volumes ONTAP in Azure."

Section: "Adding capacity to an aggregate" reiterates the process: "You can add capacity to an aggregate at any time. BlueXP adds disks to the aggregate..." This confirms that BlueXP is the designated tool for this task.

3. NetApp KB Article 1033499, "What are the supported methods to add disks to an aggregate in Cloud Volumes ONTAP?": This knowledge base article explicitly addresses the question.

Content: It confirms that the only supported method is to use the BlueXP UI or the BlueXP API. It warns that adding disks directly from the cloud provider's console (like the Azure Portal) and then adding them to the aggregate via ONTAP CLI or System Manager is an unsupported procedure.