# Check volume-root FSRM quotas when File Sync tiering never settles

> A hard quota at the volume root can make quota-restricted space disagree with physical free space and drive repeated tiering.

- Canonical URL: https://update.dsesecurity.com/updates/dse-20260909-557-check-volume-root-fsrm-quotas-when-file-sync-tiering-never-settles/
- Publisher: Detection Systems & Engineering (DSE Security)
- Author: DSE Security Editorial Team
- Published: 2026-09-10T00:22:39+00:00
- Modified: 2026-09-10T02:14:31+00:00
- Last reviewed by DSE: 2026-09-09
- Resource type: Guide
- DSE priority: Information
- Topics: Cybersecurity, Networks & Infrastructure
- Reading time: 2 minutes

## What you need to know

A hard quota at the volume root can make quota-restricted space disagree with physical free space and drive repeated tiering.

## Potentially affected

Azure File Sync cloud-tiering endpoints on volumes managed with FSRM quotas.

## DSE recommendation

Compare quota scope and physical free space before making tiering more aggressive.

## Article

## Source facts

Microsoft recommends folder-level rather than volume-level FSRM quotas for File Sync server endpoints. A hard quota at the volume root can make the quota-restricted capacity differ from actual free space. File Sync can consequently keep tiering because it perceives insufficient available space.

Cloud tiering is not supported on the Windows system volume. For supported deployments, Microsoft recommends monitoring recall volume and cache hit rate when adjusting tiering policies. [Microsoft Learn](https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-choose-cloud-tiering-policies).

## Applicability

Identify the endpoint volume, hard-quota location, quota limit and reported free space. Distinguish a quota-space mismatch from an independently established need to reduce the local cache.

## DSE recommendation

DSE recommends inspecting quota placement before repeatedly raising the free-space target or forcing more data out of cache. Coordinate any move to folder-scoped quotas with the storage owner so the intended capacity restriction remains enforced. Do not remove a quota solely to suppress symptoms without understanding what it protects. Keep the tiering policy review tied to actual access and recall observations.

## Verification

In a representative approved test, compare physical and quota-restricted space before and after the selected quota correction. Observe whether tiering behavior settles and whether the intended quota still applies. Track recall and cache-hit evidence over the agreed observation period rather than accepting a single free-space reading. Preserve continued tiering or unexpected capacity exposure as an unresolved finding.

## Official references

[Microsoft Learn: Choose Azure File Sync Cloud Tiering Policies](https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-choose-cloud-tiering-policies). Source retrieved September 9, 2026.

## Primary reference

- Name: Choose Azure File Sync Cloud Tiering Policies | Microsoft Learn
- Authority: Microsoft Learn
- URL: https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-choose-cloud-tiering-policies
- Source publication date: Not stated by the source

## Citation and use

Preferred citation: “Check volume-root FSRM quotas when File Sync tiering never settles,” DSE Security, https://update.dsesecurity.com/updates/dse-20260909-557-check-volume-root-fsrm-quotas-when-file-sync-tiering-never-settles/
Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/
Usage and citation policy: https://update.dsesecurity.com/usage/
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