Accurate Pricing for Azure Files Premium Volumes

The gap: shared volumes were mispriced

Azure gives Kubernetes two very different storage backends, and both show up as PersistentVolumes:

• Managed Disk — a block device, one pod at a time (ReadWriteOnce). CSI driver disk.csi.azure.com.
• Azure Files — a network file share over SMB/NFS, many pods at once (ReadWriteMany). CSI driver file.csi.azure.com.

We had disks priced. Azure Files had no price, so any shared (RWX) PV fell back to the wrong static rate — quietly skewing storage costs for anyone using file shares.

Why Files Premium is priceable (and EFS wasn't)

Azure Files Premium is provisioned: you declare the share size in GiB and Azure bills a flat $/GiB-month on that provisioned size, regardless of how many bytes you actually store. That provisioned size is exactly the Kubernetes PVC capacity — so:

monthly cost = rate ($/GiB-month) × PVC capacity (GiB)

That's an exact answer. It's also why we skipped AWS EFS: EFS is elastic, billed on the bytes you actually store, and the Kubernetes capacity number is essentially fictional — there's no honest way to multiply it into a cost. Azure Files Premium is the opposite, so we can price it precisely.

What we changed

• Fetcher. The pricing fetcher now also pulls Azure file-share prices (Premium only) and stores them under AzureFiles_Premium_LRS and AzureFiles_Premium_ZRS.
• Consumer routing. A shared file-share PV is routed to those rows by looking at its CSI driver (file.csi.azure.com), not the skuName alone — because the SKU name collides with managed disks.

What's covered

Standard Files stays unpriced

Standard Azure Files is pay-as-you-use (billed on stored bytes, not provisioned size), so like EFS it has no reliable per-GiB provisioned rate. We leave it unpriced rather than guess.

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What you'll see

If you run RWX workloads on Azure Files Premium, those volumes now carry a real monthly cost across the dashboard — storage totals, orphaned-volume detection, and namespace/team rollups all reflect the correct rate. No configuration needed; pricing updates automatically on the next fetch.