Compare and Contrast: NetApp Cloud Volumes ONTAP compared to Azure NetApp Files

It’s time for you to deploy in Azure. As part of your project you’ve got a bunch of NAS data you want to mange and present to various users and applications. You could stand up a virtual machine and install SMB services, but who wants to manage that? You could use Azure Files, but even Microsoft says Azure NetApp Files is the better solution. Then you got someone talking about Cloud Volumes ONTAP. Hopefully this quick article will give you the foundation to understanding the differences and decide which (or sometimes a mix) is best for your use case.

For the sake of simplicity this article is just going to cover the CVO and ANF as they exist in the Window’s Azure environment. You can also deploy CVO in Amazon’s AWS, and NetApp offers a similar ANF product in AWS called Cloud Volumes Service.

First off, what is it?

Cloud Volumes ONTAP (CVO) – “ONTAP” is the storage array software that powers NetApp’s FAS and AFF platforms. It’s loaded with tons of features including replication, storage efficiencies (duplication, compression, compaction), virtual networking & data segmentation, etc. Cloud Volumes ONTAP (previously called ONTAP Cloud, but changed because we know how nonsensical marketing is) is just the same ONTAP software – with all the same features and management functionality –  running as a virtual machine in the cloud instead of physical hardware.

Azure NetApp Files (ANF) – Deep in the bowels of Microsoft’s data centers exist a whole bunch of NetApp systems. Microsoft took the SMB functionality from those systems and translated it through the Azure market place. 99% of the ONTAP functionality is obfuscated behind that market place wall, so instead you just get a simplistic management interface for the provisioning of SMB services.


How does it compare?

(Forenote – All this is of mid 2020. The upside to cloud technologies is that there’s rapid development and updates. The downside is that I’m not constantly keeping track of some of these changes for this article. Best to reference the supporting documentation, links at the end.)

Cloud Volumes ONTAP (CVO) Azure NetApp Files (ANF)
Deployment CVO is deployed via hyperscaler integration on (though manual installations are available). A separate system called Cloud Manager gets deployed first and acts as an orchestration layer to many activities (commonly the provisioning of ONTAP instances and configuring replication).

Once Cloud Manager is deployed, a wizard will walk you through deploying a CVO instance. During deployment you will choose various instance types, drive types, networking configs, all the the basic components that make up a AWS virtual machine machine instance.

As these services run on virtual machines you deploy, you’ll have to set up things like security policies, networking, a make decisions about the resources you want to deploy behind the virtual machines.

CVO can be deployed as a single instance, or as a high availability pair (recommended).

As of me writing this, you can request access to ANF by filling out a form and getting whitelisted by NetApp (that should be depreciated by 2021). Once approved you’ll see ANF in your Azure console.
Management Management is mostly done through the Cloud Manager instance. Through it you can perform basic operations including provisioning of volumes, shares, and configuring replication between CVO and other CVO/on prem instances.

You can log into CVO directly and use the same system manager or command line interfaces. REST API support is also available.

Typically Cloud Manager has a public IP, while the CVO instances are not publicly accessible.

ANF is managed through the Azure console.

ANF supports REST API, SDK, and CLI through the Azure.

Network Access You can create multiple virtual network ports (LIFs) in different virtual networks. ANF is accessed through a special delegated subnet within your virtual network.
Region Support CVO is supported in

  • Brazil South
  • East US & East US 2
  • US Gov Virginia & Texas
  • North Central US
  • Canada Central
  • Canda East
  • South Central US
  • Central US
  • West US & West US 2
  • West Central US
  • Norway East & West
  • German North, North East, Central, and West Central
  • Switzerland North & West
  • South Africa North & West
  • UAE Central and North
  • Western Europe
  • France Central
  • United Kingdom West & South
  • Northern Europe
  • India South, Central, & West
  • Australia South East, Central, Central 2, and East
  • South East Asia
  • East Asia
  • China East, East 2, North, and North 2
  • Japan West & East
  • Korea South & Central
ANF is generally available in

  • East US & East US 2
  • Central US
  • South Central US
  • West & West US 2
  • Canada Central
  • Australia SE

Canada East support is expected in 2020.

Supported Capacity Each CVO instance can support up to 368 TB of virtual machine capacity. As far as I’m aware there is no limit to capacity tiered to Blob. Each NetApp account can support 25 capacity pools, each capacity pool can support 500 volumes, each volume can be up to 100 TiB in size.
Protocol Support CVO supports NFS, SMB, and iSCSI ANF supports NFS & SMB
Performance Characteristics CVO performance characteristics depend on both the virtual machine instance type, the type of disks behind it (ie spinning or SSD), and the workload.

A Standard_DS14_v2 instance can support up to 427 MBps streaming read with a single node. Same node can support up to 257 MBps for a streaming write workload.

ANF capacity pools have three service levels,

  • Standard – 16 MiB/s per 1 TiB quota
  • Premium – 64 MiB/s per 1 TiB quota
  • Ultra – 128 MiB/s per 1 TiB quota

Performance is stacked by stacking quotas. For example, a 10 TiB quota of Ultra storage will provide 1280 MiB/s of performance.

Data Protection ONTAP supports native snapshots, data vaulting (including WORM), as well as support for many 3rd party backup applications.

Snapshots can be scheduled and driven by policy.

CVO supports up to 1023 snaps per volume.

ANF supports the ability to take snapshots of a volume within the Azure console.

Snapshots are currently on demand.

There is support for 255 snapshots per volume.

Data Replication ONTAP volumes and Storage Virtual Machines can natively replicate (SnapMirror) between on-prem ONTAP instances and CVO instances. CVO instances can also replicate between CVO instances in or outside of the same region, and either into CVO instances deployed in other hyperscalers. There is currently no support for native replication. Replication can be performed by any number of host based file replication services.
SLA CVO SLA is going to be dependant on the backend Azure resources supporting it

  • Virtual machine SLA is 99.9% for single zone deployment
  • Virtual machine SLA is 99.95% for single resource group HA deployments
  • Blob SLA (used for tiering cold data) is 99.9% to 99.99% depending on deployment method
Azure guarantees at least 99.99% uptime.
Ownership Responsibility Customer is responsible for upgrading CVO.

Cloud Manager is generally updated automatically.

Azure owns support of the service, upgrades and additional functionality is deployed without customer interaction/involvement.
Licensing CVO can either be used on demand and charged back to NetApp via your Azure account (pay-as-you-go) or you can purchase a license up front (BYOL).

Each license supports up to 368 TB of usable capacity. If you have 600 TB of capacity spread out over local disks and tiering to blob, then you need to purchase two licenses.

There are no licensing fees for ANF.
Cost There are two costs associated with CVO, the first is the license. The second is for the Azure resources supporting it. This includes the cost of the virtual machine, the supporting storage, and any Blob capacity.

Cloud manager is free, but you have to pay Azure for the same supporting services.

ANF is charged on a capacity per hour rate depending on the performance rate. There’s a minimum purchase of 4 TiB.
Support Support for CVO is provided through NetApp. Support is provided through Azure.


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