Is Azure NetApp Files Ultra 200% more (or 50% less) than Azure Files Premium?

I’m taking strong poetic license on those “numbers,” but they’re in the ballpark. More like 240% vs 43%.

Azure NetApp Files is generally regarded as the high-performing storage platform in Azure. For most of its’ existence, ANF also substantially more expensive than Azure Files and other storage options in Azure. This has changed but it takes a little analysis to see it. I’m trying to correct the record, but old habits die hard.

Yes, Azure NetApp Files (ANF) is extremely high performing.

Yes, ANF offers the lowest possible storage latency of all storage PaaS options in Azure. Sub-millisecond means applications and databases perform better on ANF.

Yes, NetApp’s ONTAP technology that underpins ANF delivers advanced snapshot functionality. This supports instant, highly efficient, and very flexible data protection, portability and security.

No, ANF Ultra is not, I repeat, NOT more expensive that Azure Files Premium. While the top-line “price per GiB” appears to be higher (see table below), the whole story is far different. For example, here are prices from East US 2 as of today. In all my examples I’ll be comparing ANF Ultra (the highest ANF tier) to AF Premium…

Storage Solution	Price per GiB
ANF Standard	14.52 cents
ANF Premium	29.419 cents
ANF Ultra	39.274 cents
AF Premium	16.00 cents

In August ’24, Azure NetApp Files launched Azure NetApp Files storage with cool access.

This is a game changer. I’m not sure I can over-hype this. ABSOLUTE GAME CHANGER

Cool Access is a simple concept, and it is beautify executed. Data (at the block level) “warm value” is tracked by ANF, with data access reheating that value. Cool Access functionality will then automatically and seamlessly move cool blocks of data to lower cost (and yes, lower performing) storage.

When I discuss this with new users, there is a lot of confusion. Usually, the confusion stems from the user assuming this is more complicated or complex than it really is. Above I said this is “beautifully executed” and I meant it…

Behind the scenes the data is moved off of the ANF hardware to Azure Blob storage when it reaches the defined threshold. When data is accessed, it is served from blob and returned to the ANF hardware with a reheated “warm value”.

The file system’s point of view is unchanged, all files are presented to the OS, apps and users as one unified storage layer. They see no difference and have no need to change behavior in any way.

Similarly, storage administrators won’t experience changes that impact their workflows or processes. There is no separate storage account to manage, no need to change Capacity Pool or Volume sizing settings. The Azure Blob storage account used is managed by the ANF service and no administration overhead is put on the administrator for this.

Now, Of course, the administrator can make some configuration choices to make sure this feature matches their workload. In addition to the choice to enable (or not enable) Cool Access on a per-volume basis, the administrator can choose the coolness period and the Retrieval Policy.

The coolness period is simply the number of days it takes for data to be considered cool. As an administrator, you can choose between 2 and 183 days. This setting is applied at the volume level and can be changed anytime.

The Cool Access Retrieval Policy allows the administrator to define what type of data access counts towards reheating the “warm value” of a data block and currently has three options: Default, OnRead and Never. Default is a good one for most situations, it will exclude sequential reads such as AV or other file scanning operations.

Cool Access is good for many but not all workloads. You wouldn’t want to put databases that are highly latency demanding on cool storage since the retrieval of cool data from Azure Blob would certainly impact latency and the app’s ultimate performance. However, Azure Blob is still fast enough to support some real workloads, not just edge cases. General files shares and user profile data is often 80% cool.

So, how does moving 80% of ANF data from hot to cool storage impact costs? The short answer, SIGNIFICANTLY. Data on the cool tier costs just under $0.06/GiB/mo and another $0.02/GiB to transfer between hot and cool. At 80% coolness, the cost of Azure NetApp Files Ultra drops 54% with cool access from $0.39/GiB to $0.158/GiB. (remember, Azure Files Premium is $0.16/GiB). We’ll bring this all together at the end, I promise.

This one is pretty simple. (I always start a paragraph/email/message thinking this and later re-read and discover how complicated I’ve made things. Sorry, it’s how my brain works when I’m trying to commit ideas to paper, and I’m done trying to fight it)

Azure Files Premium is actually simple, it costs $0.136/GiB/month (still using the East US 2 region and today’s prices in my examples).

ANF Snapshots don’t use separate data storage, they’re simply retained on the original volume as locked data blocks that are referenced by those index/pointer files. So, we’re spending $0.39/GiB/month on snapshots? Not actually! Once the snap is taken, all existing data are essentially locked and don’t change. Further much of that data was cool (or cooling) before the snap and is already on the cool tier or headed there shortly. Taking a snap does not reheat all that data. Thus, you’re actually paying closer to $0.06/GiB/mo for snapshot data storage. (For those keeping score at home, remember that Azure Files Premium snaps are $0.136/GiB)

Azure Files Premium backups (via Azure Backup) are simply managed snapshots. So, the cost is the same as above, $0.136/GiB/mo.

ANF Backup is an Azure Backup offering that is designed to leverage (and benefit) from the ANF snapshot technology.
This one actually is simple… ANF backup cost $0.05/GiB/mo and restores cost $0.02/GiB (to cover network transfer costs behind the scenes).

As we all know, but sometimes forget, data storage involves more than just writing the data to one place. Data protection, business continuity, and performance are all contributors to the total cost of an enterprise data storage solution. Below is a basic example of how all the above commentary translates into real TCO dollars. The end result in this example is that with a top-line price of $0.39/GiB, Azure NetApp Files Ultra costs 42.5% less than Azure Files Premium, even when the top-line price of AF Premium is listed at $0.16/GiB.

Storage Solution	Active Data	Cool Data	Snapshot Data	Backup Data	Total Cost
ANF Standard – 1 TiB	$30 .2 TiB @ $0.1452/GiB	$49 .8 TiB @ $0.05986/GiB	$6 .1 TiB @ $0.06/GiB	$61 1.2 TiB @ $0.05/GiB	$146 (14.2 cents/GiB)
ANF Premium – 1 TiB	$60 .2 TiB @ $0.29419/GiB	$49 .8 TiB @ $0.05986/GiB	$6 .1 TiB @ $0.06/GiB	$61 1.2 TiB @ $0.05/GiB	$176 (17.2 cents/GiB)
ANF Ultra – 1 TiB	$80 .2 TiB @ $0.39274/GiB	$49 .8 TiB @ $0.05986/GiB	$6 .1 TiB @ $0.06/GiB	$61 1.2 TiB @ $0.05/GiB	$196 (19.1 cents/GiB)
AF Premium – 1 TiB	$160 1 TiB @ $0.16/GiB	$0 N/A	$14 .1 TiB @ $0.136/GiB	$167 1.2 TiB @ $0.136/GiB	$341 (33.3 cents/GiB)

Please don’t use these numbers for precise budgeting, this is the digital equivalent of “paper napkin math”.
To build your own comparisons use these tools:

• Azure NetApp Files Effective Price Estimator: https://aka.ms/anfeffectiveprice
• Azure NetApp Files Cool Access savings estimator: https://aka.ms/anfcoolaccesscalc
• Azure NetApp Files Pricing Page: https://azure.microsoft.com/en-us/pricing/details/netapp/
• Azure Files Premium Pricing Page: https://azure.microsoft.com/en-us/pricing/details/storage/files/

Often, I’m asked (confronted? challenged?) about the perception that I’m “attacking” Azure Files and (by proxy) Azure and Microsoft.

To be clear, and for the official record, I’m not attacking Azure Files, Azure, Microsoft or Taylor Swift (I know that seems random, but look up what happens when you trash Taylor online and you’ll understand).

I’m comparing “against” Azure Files Premium only because it is generally seen as the baseline option and is widely known and understood. It is most often the storage layer I see chosen and a good starting point for comparing and contrasting.

Also, Azure NetApp Files (like Azure Files) is Microsoft’s product, it is not a Marketplace offering or a 3rd party service. It has NetApp in the name because the service runs on NetApp hardware and software within Azure’s datacenter, but it is wholly offered, sold and supported by Microsoft. As an example, if Azure Files had the name Hitachi in the name (assuming that is the brand of HDD used, I have no idea if it is) then “Azure Hitachi Files Premium” would be just as much a Microsoft service as Azure File Premium it is today. Including a component of the value delivery chain in the name, even another company’s name like NetApp, doesn’t change the fundamental nature of that service. And thus, comparing two Azure services with each other to identify which best fits a particular use case shouldn’t be perceived as an attack on any product, service or company.

Finally, Azure Files Premium is an excellent service offering and there are many workloads and use cases where it fits perfectly. So, much love for Azure, Azure Files, Microsoft and (of course) Taylor Swift.