Find Out Which Physical Disk a Drive Letter Belongs To

**Get-Volume** shows every volume with its letter, label, file system and size. A volume without a letter is the first thing to notice.

Get-Volume | Select-Object DriveLetter,FileSystemLabel,FileSystem,HealthStatus,SizeRemaining,Size | Sort-Object DriveLetter
Get-PSDrive -PSProvider FileSystem | Select-Object Name,Root,Used,Free

**Get-Partition** carries both the drive letter and the disk number. That single table is the join between the two worlds.

Get-Partition | Select-Object DiskNumber,PartitionNumber,DriveLetter,Size,Type,IsBoot,IsActive | Sort-Object DiskNumber,PartitionNumber
Get-Partition -DriveLetter C | Format-List

**Get-Disk** adds the model, the bus type and the serial number. A disk that reports **Unhealthy** or **No Media** is the one to work on.

Get-Disk | Select-Object Number,FriendlyName,SerialNumber,BusType,HealthStatus,OperationalStatus,Size
Get-PhysicalDisk | Select-Object DeviceId,FriendlyName,MediaType,BusType,HealthStatus,SerialNumber

**Get-Disk** numbers and **Get-PhysicalDisk** DeviceIds do not always agree, especially with a RAID controller. The serial number is the stable identifier.

Get-Disk | ForEach-Object { $d=$_; $p = Get-PhysicalDisk | Where-Object SerialNumber -eq $d.SerialNumber; [pscustomobject]@{Disk=$d.Number; Model=$d.FriendlyName; Serial=$d.SerialNumber; PhysDevId=$p.DeviceId} }
Get-CimInstance Win32_DiskDrive | Select-Object Index,Model,SerialNumber,InterfaceType,Size

The partition table GUID names the disk even after it moves to another port. That is what makes a disk identifiable in a machine where the numbers changed.

Get-Disk | Select-Object Number,FriendlyName,UniqueId,Path,PartitionStyle
Get-Partition -DiskNumber 0 | Select-Object PartitionNumber,DriveLetter,Offset,GptType

A saved table turns the next incident into a lookup. Keep it next to your backup notes, because it survives a dead machine only as a file.

Get-Partition | Where-Object DriveLetter | Select-Object DriveLetter,DiskNumber,PartitionNumber,@{n='Disk';e={ (Get-Disk -Number $_.DiskNumber).FriendlyName }},@{n='Serial';e={ (Get-Disk -Number $_.DiskNumber).SerialNumber }} | Export-Csv "$env:USERPROFILE\drive-map.csv" -NoTypeInformation
Import-Csv "$env:USERPROFILE\drive-map.csv"