{"id":518,"date":"2008-08-01T00:00:27","date_gmt":"2008-08-01T08:00:27","guid":{"rendered":"http:\/\/www.sapien.com\/blog\/2008\/08\/01\/powershell-driveutilization\/"},"modified":"2016-10-27T13:50:23","modified_gmt":"2016-10-27T20:50:23","slug":"powershell-driveutilization","status":"publish","type":"post","link":"https:\/\/dev.sapien.com\/blog\/2008\/08\/01\/powershell-driveutilization\/","title":{"rendered":"PowerShell: DriveUtilization"},"content":{"rendered":"

The other day I posted a VBS function<\/a> for getting drive utilization. It seems only fair to give PowerShell a chance to play.<\/p>\n

\n
\n
   1:<\/span> Function Get-Utilization {<\/pre>\n
   2:<\/span>     Param([string]$computername=$env:computername,<\/pre>\n
   3:<\/span>           [string]$ID=\"C:\"<\/span><\/pre>\n
   4:<\/span>           )<\/pre>\n
   5:<\/span><\/pre>\n
   6:<\/span>      #suppress errors messages    <\/span><\/pre>\n
   7:<\/span>     $errorActionPreference=\"silentlycontinue\"<\/span><\/pre>\n
   8:<\/span><\/pre>\n
   9:<\/span>     $drive=Get-WmiObject Win32_Logicaldisk -filter<\/span> \"DeviceID='$ID'\"<\/span> `<\/pre>\n
  10:<\/span>     -computername $computername -errorAction \"silentlycontinue\"<\/span><\/pre>\n
  11:<\/span><\/pre>\n
  12:<\/span>     if<\/span> ($drive.size) {<\/pre>\n
  13:<\/span><\/pre>\n
  14:<\/span>         #divide size and freespace by 1MB because they are UInt64<\/span><\/pre>\n
  15:<\/span>         #and I can't do anything with them in there native type<\/span><\/pre>\n
  16:<\/span><\/pre>\n
  17:<\/span>         $size=$drive.size\/1MB<\/pre>\n
  18:<\/span>         $free=$drive.freespace\/1MB<\/pre>\n
  19:<\/span><\/pre>\n
  20:<\/span>         $utilization=($size-$free)\/$size<\/pre>\n
  21:<\/span><\/pre>\n
  22:<\/span>         write $utilization<\/pre>\n
  23:<\/span>     }<\/pre>\n
  24:<\/span>     else<\/span> {<\/pre>\n
  25:<\/span>     #there as an error so return a value that can't be mistaken<\/span><\/pre>\n
  26:<\/span>     #for drive utilization<\/span><\/pre>\n
  27:<\/span>         write -1<\/pre>\n
  28:<\/span>     }<\/pre>\n
  29:<\/span><\/pre>\n
  30:<\/span> }<\/pre>\n
  31:<\/span><\/pre>\n
  32:<\/span> #Sample usage<\/span><\/pre>\n
  33:<\/span> $computer=\"PUCK\"<\/span><\/pre>\n
  34:<\/span> $drive=\"C:\"<\/span><\/pre>\n
  35:<\/span> $u=Get-Utilization $computer $drive<\/pre>\n
  36:<\/span><\/pre>\n
  37:<\/span> #format $u as a percentage to 2 decimal points<\/span><\/pre>\n
  38:<\/span><\/pre>\n
  39:<\/span> $percent=\"{0:P2}\"<\/span> -f $u<\/pre>\n
  40:<\/span><\/pre>\n
  41:<\/span> if<\/span> ($u -eq<\/span> -1) {<\/pre>\n
  42:<\/span>     $msg=\"WARNING: Failed to get drive {0} on {1}\"<\/span> -f $drive,$computer<\/pre>\n
  43:<\/span>     $color=\"RED\"<\/span><\/pre>\n
  44:<\/span> }<\/pre>\n
  45:<\/span> elseif<\/span> ($u -ge<\/span> .75) {<\/pre>\n
  46:<\/span>     $msg=\"WARNING: Drive {0} on {1} is at {2} utilization.\"<\/span> -f $drive,$computer,$percent<\/pre>\n
  47:<\/span>     $color=\"RED\"<\/span><\/pre>\n
  48:<\/span> }<\/pre>\n
  49:<\/span> else<\/span> {<\/pre>\n
  50:<\/span>     $msg=\"WARNING: Drive {0} on {1} is at {2} utilization.\"<\/span> -f $drive,$computer,$percent<\/pre>\n
  51:<\/span>     $color=\"GREEN\"<\/span><\/pre>\n
  52:<\/span> }<\/pre>\n
  53:<\/span><\/pre>\n
  54:<\/span> Write-Host $msg -foregroundcolor $color<\/pre>\n<\/div>\n<\/div>\n
The Get-Utilization function also uses WMI via the Get-WMIObject cmdlet. One nice advantage to PowerShell is that I can specify default parameter values. I’ve set the defaults to the %computername% environmental variable and drive C:\\. To make the function as seamless as possible, I turn off the error pipeline by setting $ErrorActionPreference to SilentlyContinue. I do the same with the -ErrorAction parameter in line 18.\u00a0 If the Get-WMIObject expression is successful, then $drive.size will have a value and I can carry out my utilization calculations. If it doesn’t exist then there was some problem, perhaps permissions or an invalid drive, in this function I don’t really care. Instead I’ll simply return a value that can’t be mistaken for a drive utilization at line 27.<\/p>\n
Assuming a valid drive object was returned I perform a similar calculation as I did in VBScript and write the result to the pipeline. Line 33 shows the function in use. I use an If ElseIf construct to display an appropriate message depending on the value returned by Get-Utilization. Another advantage over VBScript is that I can display the message in a different color depending on the utilization value.<\/p>\n
You’re welcome to expand the function. For example, there is no provision for alternate credentials. You could probably add more error handling. I have to leave some fun for you right?<\/p>\n
\n
Download the PowerShell file here.<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
The other day I posted a VBS function for getting drive utilization. It seems only fair to give PowerShell a chance to play.<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[25],"tags":[198,249,28,57,248,250,35],"class_list":["post-518","post","type-post","status-publish","format-standard","hentry","category-windows-powershell","tag-function","tag-get-wmiobject","tag-powershell","tag-scripting","tag-utilization","tag-win32_logicaldisk","tag-wmi"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts\/518","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/comments?post=518"}],"version-history":[{"count":1,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts\/518\/revisions"}],"predecessor-version":[{"id":12766,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/posts\/518\/revisions\/12766"}],"wp:attachment":[{"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/media?parent=518"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/categories?post=518"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dev.sapien.com\/blog\/wp-json\/wp\/v2\/tags?post=518"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}