Get-S2DVolumeMap¶

Maps all S2D volumes (virtual disks) with resiliency type, pool footprint, efficiency percentage, provisioning type, and infrastructure volume classification.

Syntax¶

Get-S2DVolumeMap [[-VolumeName] <string[]>] [[-CimSession] <CimSession>]

Parameters¶

Parameter	Type	Description
`-VolumeName`	`string[]`	Limit results to specific volume friendly names.
`-CimSession`	`CimSession`	Override the module session CimSession.

Output¶

Returns S2DVolume[] — one object per virtual disk.

Property	Type	Description
`FriendlyName`	`string`	Volume name
`FileSystem`	`string`	`CSVFS_ReFS`, `CSVFS_NTFS`, or `Unknown`
`ResiliencySettingName`	`string`	`Mirror` or `Parity`
`NumberOfDataCopies`	`int`	Data copy count (2 = two-way, 3 = three-way)
`PhysicalDiskRedundancy`	`int`	Disk failure tolerance
`ProvisioningType`	`string`	`Fixed` or `Thin`
`Size`	`S2DCapacity`	Logical volume size (what VMs see)
`FootprintOnPool`	`S2DCapacity`	Actual pool space consumed (includes resiliency overhead)
`AllocatedSize`	`S2DCapacity`	Bytes written to the volume (thin volumes only)
`OperationalStatus`	`string`	`OK`, `InService`, `Online`, or error state
`HealthStatus`	`string`	`Healthy`, `Warning`, or `Unhealthy`
`IsDeduplicationEnabled`	`bool`	Whether deduplication is active
`IsInfrastructureVolume`	`bool`	Azure Local infrastructure volume detection (see below)
`EfficiencyPercent`	`double`	Resiliency efficiency (logical ÷ footprint × 100)
`OvercommitRatio`	`double`	Thin overcommit ratio for this volume (`AllocatedSize ÷ FootprintOnPool`)
`ThinGrowthHeadroom`	`S2DCapacity`	Remaining write headroom before pool footprint equals provisioned size: `Size − AllocatedSize`. `$null` for fixed-provisioned volumes.
`MaxPotentialFootprint`	`S2DCapacity`	Maximum pool space this volume could consume if written completely full: `Size × NumberOfDataCopies`. `$null` for fixed-provisioned volumes.

Resiliency Efficiency¶

EfficiencyPercent is computed per volume based on resiliency type and node count:

Configuration	`EfficiencyPercent`
Two-way mirror	50.0
Three-way mirror	33.3
Nested two-way mirror (2-node)	25.0
Single parity	66.7 (4-node) / 75.0 (6-node)
Dual parity (LRC)	50.0 (4-node) / 66.7 (6-node)

The blended efficiency across all workload volumes is reported as BlendedEfficiencyPercent on the S2DCapacityWaterfall object.

Infrastructure Volume Detection¶

Azure Local automatically creates one or more infrastructure volumes for cluster metadata, storage bus layer logs, and CSV cache. Get-S2DVolumeMap detects these volumes and sets IsInfrastructureVolume = $true using two signals:

Name pattern match (any of):

Infrastructure_<guid> — Azure Local infrastructure CSV
ClusterPerformanceHistory — storage performance history
Any name containing infra or infrastructure

Size heuristic:

Volumes smaller than 600 GiB are flagged as infrastructure volumes

Infrastructure volume in capacity math

The infrastructure volume footprint is broken out in Stage 5 of the capacity waterfall so that it does not inflate the workload usable capacity figure. Use Where-Object IsInfrastructureVolume -eq $false to see workload volumes only.

CIM Sources¶

Get-VirtualDisk

Volume objects are constructed from VirtualDisk WMI properties. File system type is inferred from the filesystem field; cluster shared volume association is implied by the CSV namespace path.

Session Behavior¶

Results are cached in $Script:S2DSession.CollectedData['Volumes'] after first collection. Get-S2DCapacityWaterfall and Get-S2DHealthStatus read from this cache.

When -VolumeName is specified, the filter is applied after caching — all volumes are cached, but only the requested ones are returned to the caller.

Examples¶

# All volumes with key properties
Get-S2DVolumeMap | Format-Table FriendlyName, ResiliencySettingName, Size, FootprintOnPool, EfficiencyPercent, IsInfrastructureVolume

# Workload volumes only
Get-S2DVolumeMap | Where-Object IsInfrastructureVolume -eq $false

# Thin-provisioned volumes with overcommit
Get-S2DVolumeMap | Where-Object ProvisioningType -eq 'Thin' | Format-Table FriendlyName, Size, AllocatedSize, OvercommitRatio

# Thin provisioning risk — max potential footprint vs current pool footprint
Get-S2DVolumeMap |
    Where-Object { $_.ProvisioningType -eq 'Thin' -and $_.MaxPotentialFootprint } |
    Format-Table FriendlyName, Size, ThinGrowthHeadroom, MaxPotentialFootprint, AllocatedSize

# Unhealthy volumes
Get-S2DVolumeMap | Where-Object HealthStatus -ne 'Healthy' | Format-List

# Single volume detail
Get-S2DVolumeMap -VolumeName "VM-Storage-01" | Format-List

Troubleshooting¶

No volumes returned

If the command emits No virtual disks found, either no volumes have been created yet or the PSSession cannot see them. Verify on a cluster node:

Get-VirtualDisk | Format-Table FriendlyName, OperationalStatus, HealthStatus

Usable Capacity (Stage 7) is zero after Get-S2DCapacityWaterfall

If the final usable capacity is 0 TiB, no workload volumes were found — either all volumes are classified as infrastructure, or Get-S2DVolumeMap returned no results. Check:

Get-S2DVolumeMap | Format-Table FriendlyName, IsInfrastructureVolume, Size

If all show IsInfrastructureVolume = $true, verify that workload CSV volumes have been created.