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When attempting to create a new NetApp volume, an error occurs related to an "unexpected property for volumeProperties (PreFlightDeserializationError)". This error persists using any NetApp file or capacity pool. The issue began yesterday as my last attempt, to create a volume successfully, was on Friday. As of Monday, the volume fails to be created with the following validation error on every attempt:
{
"code": "InvalidTemplateDeployment",
"message": "The template deployment 'CreateVolume-20251015101218' is not valid according to the validation procedure. The tracking id is 'b3d16d90-d86f-4723-9d27-e99a0b86d84a'. See inner errors for details.",
"details": [
{
"code": "PreFlightDeserializationError",
"target": "/subscriptions/238e2553-79cb-45ed-b57d-2d6a4b8c2e85/resourceGroups/tr-intuition-cluster/providers/Microsoft.NetApp/netAppAccounts/NetAppDev/capacityPools/newUltra/volumes/tempvol",
"message": "Validation error for Microsoft.NetApp/netAppAccounts/capacityPools/volumes: '/subscriptions/238e2553-79cb-45ed-b57d-2d6a4b8c2e85/resourceGroups/tr-intuition-cluster/providers/Microsoft.NetApp/netAppAccounts/NetAppDev/capacityPools/newUltra/volumes/tempvol': Unexpected property 'breakthroughMode' received for 'volumeProperties'. Path 'breakthroughMode', line 21, position 21. (This property is available in Api-Version 2025-08-01-preview and later). Please check the input model and Api-Version 2025-08-01 are correct based on the requirements of the endpoint and try again."
}
]
}
An Azure service that provides enterprise-grade file shares powered by NetApp.
Hello Michael Wilkerson,
Sorry to hear you’re running into issues when creating a new NetApp volume. Based on the error message you shared—“Unexpected property 'breakthroughMode' received for 'volumeProperties'. This property is available in Api-Version 2025-08-01-preview and later. Please check the input model and Api-Version 2025-08-01 are correct based on the requirements of the endpoint and try again”—it looks like the template deployment is using a property (breakthroughMode) that isn’t recognized in your current API version.
Here are a few steps you can try:
Check the API Version: Make sure your deployment template or request is set to use the API version 2025-08-01-preview or later, as breakthroughMode is only supported starting from that version.
Remove or Update the Property: If you can't use the preview API, remove the breakthroughMode property from your template or payload, then try your deployment again.
Validate the Template: Review your ARM template or API call for any properties not supported by your target API version. Use Azure’s ARM template validation tools to check for such issues.
Documentation Reference: Check the official Azure NetApp Files REST API documentation for details on supported properties and versions.
If updating the API version or removing the property doesn’t resolve the issue, please share your template snippet and deployment steps for further examination.
Best regards,
Jerald Felix
Thanks Jerald,
I am using the GUI to create the volume. There is no template involved. It fails during validation. Is an API being triggered in the background?
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Hello Michael,
Could you please check the private mesaage and share us the requested details?
Hello Michael,
Could you please check the private message and share us the requested details?
Further troubleshooting confirmed this issue affected Standard, Premium, and Ultra pools. The workaround was to use a Flex pool.
The issue resolved, on its own, a week later. The root cause was not identified.