disk-storage

name	disk-storage
description	Analyze disk space, volume health, and storage capacity on Windows Servers

Disk Storage - Disk Space and Health Analysis

Purpose

Analyze disk storage including volume space, disk health, SMART data, and identify potential storage issues.

PowerShell Code

Complete Disk Storage Analysis

$ServerName = "TARGET_SERVER"
# For current user (default): no credential needed
# For explicit credentials: check if $credential variable exists (user must create BEFORE running gh copilot)

$scriptBlock = {
    try {
        # Get volume information
        $volumes = Get-Volume | Where-Object { $_.DriveLetter -or $_.FileSystemLabel }
        
        $volumeData = foreach ($vol in $volumes) {
            $driveLetter = if ($vol.DriveLetter) { "$($vol.DriveLetter):" } else { "N/A" }
            
            [PSCustomObject]@{
                DriveLetter     = $driveLetter
                FileSystemLabel = $vol.FileSystemLabel
                FileSystem      = $vol.FileSystem
                SizeGB          = [math]::Round($vol.Size / 1GB, 2)
                FreeGB          = [math]::Round($vol.SizeRemaining / 1GB, 2)
                UsedGB          = [math]::Round(($vol.Size - $vol.SizeRemaining) / 1GB, 2)
                PercentFree     = [math]::Round(($vol.SizeRemaining / $vol.Size) * 100, 2)
                HealthStatus    = $vol.HealthStatus
                OperationalStatus = $vol.OperationalStatus
            }
        }
        
        # Get physical disk information
        $physicalDisks = Get-PhysicalDisk -ErrorAction SilentlyContinue
        
        $diskData = foreach ($disk in $physicalDisks) {
            [PSCustomObject]@{
                FriendlyName      = $disk.FriendlyName
                MediaType         = $disk.MediaType
                BusType           = $disk.BusType
                SizeGB            = [math]::Round($disk.Size / 1GB, 2)
                HealthStatus      = $disk.HealthStatus
                OperationalStatus = $disk.OperationalStatus
                Usage             = $disk.Usage
                SerialNumber      = $disk.SerialNumber
            }
        }
        
        # Get partition information
        $partitions = Get-Partition -ErrorAction SilentlyContinue | Where-Object { $_.DriveLetter }
        
        $partitionData = foreach ($part in $partitions) {
            [PSCustomObject]@{
                DriveLetter   = "$($part.DriveLetter):"
                PartitionNumber = $part.PartitionNumber
                SizeGB        = [math]::Round($part.Size / 1GB, 2)
                Type          = $part.Type
                IsSystem      = $part.IsSystem
                IsActive      = $part.IsActive
                IsBoot        = $part.IsBoot
            }
        }
        
        # Check for low disk space
        $lowSpace = $volumeData | Where-Object { $_.PercentFree -lt 15 -and $_.SizeGB -gt 1 }
        $criticalSpace = $volumeData | Where-Object { $_.PercentFree -lt 5 -and $_.SizeGB -gt 1 }
        
        # Check for unhealthy disks
        $unhealthyDisks = $diskData | Where-Object { $_.HealthStatus -ne "Healthy" }
        
        [PSCustomObject]@{
            Volumes          = $volumeData
            PhysicalDisks    = $diskData
            Partitions       = $partitionData
            LowSpaceVolumes  = $lowSpace
            CriticalSpaceVolumes = $criticalSpace
            UnhealthyDisks   = $unhealthyDisks
            Timestamp        = Get-Date
        }
        
    } catch {
        throw "Disk storage analysis failed: $($_.Exception.Message)"
    }
}

try {
    $invokeParams = @{
        ComputerName = $ServerName
        ScriptBlock  = $scriptBlock
        ErrorAction  = 'Stop'
    UseSSL        = $true
    Port          = 5986
    SessionOption = (New-PSSessionOption -SkipCACheck -SkipCNCheck)
    }
    
    if ($credential) {
        $invokeParams['Credential'] = $credential
    }
    
    Write-Host "`nAnalyzing disk storage on $ServerName..." -ForegroundColor Cyan
    $result = Invoke-Command @invokeParams
    
    Write-Host "`n=== Volume Information ===" -ForegroundColor Yellow
    $result.Volumes | Format-Table DriveLetter, FileSystemLabel, SizeGB, FreeGB, PercentFree, HealthStatus -AutoSize
    
    Write-Host "`n=== Physical Disks ===" -ForegroundColor Yellow
    $result.PhysicalDisks | Format-Table FriendlyName, MediaType, BusType, SizeGB, HealthStatus, OperationalStatus -AutoSize
    
    if ($result.CriticalSpaceVolumes) {
        Write-Host "`n⚠ CRITICAL: Volumes with <5% free space!" -ForegroundColor Red
        $result.CriticalSpaceVolumes | Format-Table DriveLetter, FileSystemLabel, FreeGB, PercentFree -AutoSize
    }
    
    if ($result.LowSpaceVolumes) {
        Write-Host "`n⚠ WARNING: Volumes with <15% free space" -ForegroundColor Yellow
        $result.LowSpaceVolumes | Format-Table DriveLetter, FileSystemLabel, FreeGB, PercentFree -AutoSize
    }
    
    if ($result.UnhealthyDisks) {
        Write-Host "`n⚠ UNHEALTHY DISKS DETECTED!" -ForegroundColor Red
        $result.UnhealthyDisks | Format-Table FriendlyName, HealthStatus, OperationalStatus -AutoSize
        Write-Host "  → Immediate action required! Backup data and replace disk." -ForegroundColor Yellow
    }
    
    if (-not $result.CriticalSpaceVolumes -and -not $result.LowSpaceVolumes -and -not $result.UnhealthyDisks) {
        Write-Host "`n✓ All disks healthy with adequate free space" -ForegroundColor Green
    }
    
    # Return full result
    $result
    
} catch {
    Write-Error "Failed to analyze disk storage on $ServerName : $($_.Exception.Message)"
}

Get SMART Data (Physical Disk Health)

$ServerName = "TARGET_SERVER"
# For current user (default): no credential needed
# For explicit credentials: check if $credential variable exists (user must create BEFORE running gh copilot)

$scriptBlock = {
    try {
        # Get SMART data via Storage cmdlets
        $disks = Get-PhysicalDisk
        
        $smartData = foreach ($disk in $disks) {
            $reliability = Get-StorageReliabilityCounter -PhysicalDisk $disk -ErrorAction SilentlyContinue
            
            [PSCustomObject]@{
                DiskNumber        = $disk.DeviceId
                FriendlyName      = $disk.FriendlyName
                MediaType         = $disk.MediaType
                HealthStatus      = $disk.HealthStatus
                Temperature       = $reliability.Temperature
                Wear              = $reliability.Wear
                ReadErrors        = $reliability.ReadErrorsTotal
                WriteErrors       = $reliability.WriteErrorsTotal
                PowerOnHours      = $reliability.PowerOnHours
                StartStopCycles   = $reliability.StartStopCycleCount
            }
        }
        
        $smartData
        
    } catch {
        throw "SMART data collection failed: $($_.Exception.Message)"
    }
}

try {
    $invokeParams = @{
        ComputerName = $ServerName
        ScriptBlock  = $scriptBlock
        ErrorAction  = 'Stop'
    UseSSL        = $true
    Port          = 5986
    SessionOption = (New-PSSessionOption -SkipCACheck -SkipCNCheck)
    }
    
    if ($credential) {
        $invokeParams['Credential'] = $credential
    }
    
    Write-Host "`nRetrieving SMART data from $ServerName..." -ForegroundColor Cyan
    $smartData = Invoke-Command @invokeParams
    
    if ($smartData) {
        Write-Host "`n=== SMART Data / Disk Health ===" -ForegroundColor Yellow
        $smartData | Format-Table FriendlyName, MediaType, HealthStatus, Temperature, 
            PowerOnHours, ReadErrors, WriteErrors -AutoSize
        
        # Check for issues
        $hotDisks = $smartData | Where-Object { $_.Temperature -gt 60 }
        $errorDisks = $smartData | Where-Object { $_.ReadErrors -gt 0 -or $_.WriteErrors -gt 0 }
        
        if ($hotDisks) {
            Write-Host "`n⚠ Disks running hot (>60°C):" -ForegroundColor Yellow
            $hotDisks | Format-Table FriendlyName, Temperature -AutoSize
        }
        
        if ($errorDisks) {
            Write-Host "`n⚠ Disks with read/write errors:" -ForegroundColor Red
            $errorDisks | Format-Table FriendlyName, ReadErrors, WriteErrors -AutoSize
            Write-Host "  → These disks may be failing. Backup and replace immediately." -ForegroundColor Yellow
        }
    } else {
        Write-Host "`nSMART data not available (may not be supported on this system)" -ForegroundColor Yellow
    }
    
    $smartData
    
} catch {
    Write-Warning "SMART data retrieval failed: $($_.Exception.Message)"
}

Find Large Files/Folders

$ServerName = "TARGET_SERVER"
# For current user (default): no credential needed
# For explicit credentials: check if $credential variable exists (user must create BEFORE running gh copilot)
$DriveLetter = "C"
$TopN = 20

Write-Host "Finding largest items on ${DriveLetter}: drive..." -ForegroundColor Cyan
Write-Host "Note: This can take several minutes on large volumes" -ForegroundColor Yellow

$scriptBlock = {
    param($drive, $top)
    
    try {
        # Find largest folders
        $folders = Get-ChildItem -Path "${drive}:\" -Directory -Force -ErrorAction SilentlyContinue |
            ForEach-Object {
                $size = (Get-ChildItem -Path $_.FullName -Recurse -File -Force -ErrorAction SilentlyContinue |
                    Measure-Object -Property Length -Sum -ErrorAction SilentlyContinue).Sum
                
                [PSCustomObject]@{
                    Type   = "Folder"
                    Path   = $_.FullName
                    SizeGB = [math]::Round($size / 1GB, 2)
                }
            } | Sort-Object SizeGB -Descending | Select-Object -First $top
        
        # Find largest files
        $files = Get-ChildItem -Path "${drive}:\" -File -Recurse -Force -ErrorAction SilentlyContinue |
            Sort-Object Length -Descending |
            Select-Object -First $top |
            ForEach-Object {
                [PSCustomObject]@{
                    Type   = "File"
                    Path   = $_.FullName
                    SizeGB = [math]::Round($_.Length / 1GB, 2)
                }
            }
        
        # Combine and return top items
        ($folders + $files) | Sort-Object SizeGB -Descending | Select-Object -First $top
        
    } catch {
        throw "Large file search failed: $($_.Exception.Message)"
    }
}

try {
    $invokeParams = @{
        ComputerName = $ServerName
        ScriptBlock  = $scriptBlock
        ArgumentList = @($DriveLetter, $TopN)
        ErrorAction  = 'Stop'
    UseSSL        = $true
    Port          = 5986
    SessionOption = (New-PSSessionOption -SkipCACheck -SkipCNCheck)
    }
    
    if ($credential) {
        $invokeParams['Credential'] = $credential
    }
    
    $largeItems = Invoke-Command @invokeParams
    
    Write-Host "`n=== Top $TopN Largest Items on ${DriveLetter}: ===" -ForegroundColor Yellow
    $largeItems | Format-Table Type, SizeGB, Path -AutoSize
    
    $largeItems
    
} catch {
    Write-Error "Failed to find large files: $($_.Exception.Message)"
}

Check Disk I/O Statistics

$ServerName = "TARGET_SERVER"
# For current user (default): no credential needed
# For explicit credentials: check if $credential variable exists (user must create BEFORE running gh copilot)

$scriptBlock = {
    try {
        $logicalDisks = Get-CimInstance Win32_LogicalDisk | Where-Object { $_.DriveType -eq 3 }
        
        foreach ($disk in $logicalDisks) {
            $perfData = Get-Counter "\LogicalDisk($($disk.DeviceID))\*" -ErrorAction SilentlyContinue
            
            if ($perfData) {
                $samples = $perfData.CounterSamples
                
                [PSCustomObject]@{
                    Drive             = $disk.DeviceID
                    ReadsPerSec       = [math]::Round(($samples | Where-Object { $_.Path -like "*Disk Reads/sec" }).CookedValue, 2)
                    WritesPerSec      = [math]::Round(($samples | Where-Object { $_.Path -like "*Disk Writes/sec" }).CookedValue, 2)
                    AvgDiskSecRead    = [math]::Round(($samples | Where-Object { $_.Path -like "*Avg. Disk sec/Read" }).CookedValue * 1000, 2)
                    AvgDiskSecWrite   = [math]::Round(($samples | Where-Object { $_.Path -like "*Avg. Disk sec/Write" }).CookedValue * 1000, 2)
                    DiskQueueLength   = [math]::Round(($samples | Where-Object { $_.Path -like "*Avg. Disk Queue Length" }).CookedValue, 2)
                }
            }
        }
        
    } catch {
        throw "Disk I/O statistics failed: $($_.Exception.Message)"
    }
}

try {
    $invokeParams = @{
        ComputerName = $ServerName
        ScriptBlock  = $scriptBlock
        ErrorAction  = 'Stop'
    UseSSL        = $true
    Port          = 5986
    SessionOption = (New-PSSessionOption -SkipCACheck -SkipCNCheck)
    }
    
    if ($credential) {
        $invokeParams['Credential'] = $credential
    }
    
    Write-Host "`nDisk I/O Performance:" -ForegroundColor Cyan
    $ioStats = Invoke-Command @invokeParams
    
    $ioStats | Format-Table Drive, ReadsPerSec, WritesPerSec, 
        @{L='ReadLatency(ms)';E={$_.AvgDiskSecRead}}, 
        @{L='WriteLatency(ms)';E={$_.AvgDiskSecWrite}}, 
        DiskQueueLength -AutoSize
    
    $slowDisks = $ioStats | Where-Object { $_.AvgDiskSecRead -gt 20 -or $_.AvgDiskSecWrite -gt 20 }
    if ($slowDisks) {
        Write-Host "`n⚠ Slow disks detected (latency >20ms):" -ForegroundColor Yellow
        $slowDisks | Format-Table Drive, @{L='ReadLatency(ms)';E={$_.AvgDiskSecRead}}, 
            @{L='WriteLatency(ms)';E={$_.AvgDiskSecWrite}} -AutoSize
    }
    
    $ioStats
    
} catch {
    Write-Error "Failed to get disk I/O statistics: $($_.Exception.Message)"
}

Interpreting Results

Disk Space Thresholds

Free Space	Status	Action Required
>20%	Healthy	Monitor regularly
10-20%	Warning	Plan cleanup or expansion
5-10%	Critical	Immediate action needed
<5%	Emergency	System may become unstable

Special Volume Considerations

• System (C:): Keep >15% free for updates, temp files, crash dumps
• Database volumes: Keep >20% free for growth, index rebuilds
• Log volumes: Monitor actively; logs can fill rapidly

Health Status Meanings

Status	Meaning	Action
Healthy	Normal operation	None
Warning	Predictive failure detected	Backup and monitor closely
Unhealthy	Disk failing	Replace immediately
Unknown	Cannot determine health	Investigate

SMART Indicators

Temperature

• <50°C: Normal
• 50-60°C: Acceptable

• 60°C: Hot (check cooling, may shorten lifespan)

Read/Write Errors

• 0: Good

• 0: Disk problems; potential failure

Power-On Hours

• Consumer drives: ~40,000 hours (~4.5 years) typical lifespan
• Enterprise drives: ~100,000+ hours

I/O Performance

Metric	SSD Good	HDD Good	Problem
Read Latency	<10ms	<15ms	>50ms
Write Latency	<10ms	<15ms	>50ms
Queue Length	<1	<2	>5

Common Issues

Disk Full

Causes: Log files, temp files, backups, page file, hibernation file Quick wins: Clean temp, old logs, Windows Update cleanup, disk cleanup utility

Disk Fragmentation (HDD only)

Symptoms: Slow performance, high latency Action: Defragmentation (not needed on SSDs)

Failing Disk

Symptoms: Unhealthy status, SMART errors, slow performance, clicking sounds Action: Backup immediately, replace disk

Storage Configuration Issues

Symptoms: Single large volume, no redundancy Action: Consider RAID, multiple volumes for better management

Error Handling

# Gracefully handle missing cmdlets or permissions
$ServerName = "TARGET_SERVER"

try {
    $result = Invoke-Command -ComputerName $ServerName -UseSSL -Port 5986 -SessionOption (New-PSSessionOption -SkipCACheck -SkipCNCheck) -ScriptBlock {
        try {
            Get-Volume | Select-Object DriveLetter, 
                @{L='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, 
                @{L='FreeGB';E={[math]::Round($_.SizeRemaining/1GB,2)}}, 
                HealthStatus
        } catch {
            # Fallback to WMI if Storage cmdlets unavailable
            Get-CimInstance Win32_LogicalDisk | Where-Object { $_.DriveType -eq 3 } |
                Select-Object DeviceID, 
                    @{L='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, 
                    @{L='FreeGB';E={[math]::Round($_.FreeSpace/1GB,2)}}
        }
    } -ErrorAction Stop
    
    $result | Format-Table -AutoSize
    
} catch {
    Write-Error "Disk check failed: $($_.Exception.Message)"
}

Next Steps

Based on disk analysis:

• Low space → Find large files, clean up, or expand volume
• Unhealthy disk → Immediate backup and replacement
• High I/O latency → Check performance counters for bottleneck confirmation
• SMART errors → Replace disk before failure
• Log growth → Check services and applications generating logs