Randomize Windows Updates via PowerShell and PSWindowsUpdate

# Purpose: Use the PowerShell Windows Update to install a few random updates and reboot
# Requirements: Module must be copied to and run on local machine
# Source: https://gallery.technet.microsoft.com/scriptcenter/2d191bcd-3308-4edd-9de2-88dff796b0bc
# Network Share: \\server\Scripts\WindowsUpdates\PSWindowsUpdateScripts\install-random-updates-reboot.ps1
# Implementation: Group Policy could copy module to client, Group Policy could create a Schedule Task to run script when idle
# Author: Jason Pearce created this script (not the module)
# Date: 2016 Feb 2
# Version: 2.1
 
# ####################
# BEGIN Variables
# ####################
 
# Count: Define how many random updates with KB values you want to install
$WUCount = 0
 
# Module Source Path: The network share that contains the PowerShell Windows Update module
$WUModuleSourcePath = '\\server\Scripts\WindowsUpdates\PSWindowsUpdate\*'
 
# Logs Local Path: The local path to write logs
$WULocalLogPath = $ENV:SystemDrive+'\PSLogs'
 
# Logs Network Path: The network path to copy logs as a central repository
$WUNetworkLogPath = '\\server\ActivityLogs\PSWindowsUpdate\Computers\'
 
# Logs Network Shortcut Path: The network path to create shortcuts to local administrative shares
$WUNetworkShortcutPath = '\\server\ActivityLogs\PSWindowsUpdate\LocalPSLogsFolders\'
 
# ####################
# END Variables
# ####################
 
# Copy Module: Copy module to client IF it does not already exist
$WUModuleDestinationPath = $ENV:SystemRoot+'\System32\WindowsPowerShell\v1.0\Modules\PSWindowsUpdate'
IF ( -Not (Test-Path -Path $WUModuleDestinationPath)) {New-Item $WUModuleDestinationPath -ItemType Directory; Copy-Item -Path $WUModuleSourcePath -Destination $WUModuleDestinationPath -Recurse -Force}
 
# Import Module: Import the Powershell Windows Update module
Import-Module PSWindowsUpdate
 
# Date: Get the date and time in a filename friendly format
$WUDate = Get-Date -Format yyyyMMdd-HHmmss
 
# Log Folder: Create a log folder IF it does not already exist
IF ( -Not (Test-Path -Path $WULocalLogPath)) {New-Item -Path $WULocalLogPath -ItemType Directory}
 
# Log Filename: Create a log filename for module, computer name, date, and time
$WULogFile = $WULocalLogPath+'\PSWinUp-'+$ENV:ComputerName+'-'+$WUDate+'.log'
 
# Log Header: Create log file with header and time stamp
$WUNewLine = "`r`n"
$WUNewBreak = "===================="
$WULogHeader = $WUNewBreak + $WUNewLine + "Begin: " + $WUDate + $WUNewLine + $WUNewBreak
 
# Create Shortcut:Create a Shortcut on a network share to the PSLogs folder
$WUTargetFile = '\\'+$ENV:ComputerName+'\C$\PSLogs'
$WUShortcutFile = $WUNetworkShortcutPath+$ENV:ComputerName+'-PSLogsFolder.lnk'
$WUWScriptShell = New-Object -ComObject WScript.Shell
$WUShortcut = $WUWScriptShell.CreateShortcut($WUShortcutFile)
$WUShortcut.TargetPath = $WUTargetFile
$WUShortcut.Save()
 
# List All Updates: Get a list of all updates
$WUAllUpdates = Get-WUList
 
# List Random Updates: Filter updates that do/don't have a KB number, randomize them, output the defined count, then convert list to comma-delimited string
$WURandomUpdatesWithKB = ($WUAllUpdates | Where-Object {$_.KB -like "KB*"} | Select-Object -Expand KB | Get-Random -Count $WUCount) -join ","
$WURandomUpdatesWithoutKB = ($WUAllUpdates | Where-Object {$_.KB -notlike "KB*"} | Select-Object -Expand Title | Get-Random -Count $WUCount) -join ","
 
# Measure Updates: Count how many updates were selected ($_.Count will be used later)
$WUMeasuredAllUpdates = $WUAllUpdates | Measure-Object
$WUMeasuredUpdatesWithKB = $WUAllUpdates | Where-Object {$_.KB -like "KB*"} | Measure-Object
$WUMeasuredUpdatesWithoutKB = $WUAllUpdates | Where-Object {$_.KB -notlike "KB*"} | Measure-Object
 
# IF the correct quantity of random updates are needed, install them. ELSEIF, install all remaining updates if any. ELSE, do nothing and exit.
IF ($WUMeasuredUpdatesWithKB.Count -eq $WUCount)
{
	# IF: If there are X needed random updates, install those X updates.
 
	# Log Header: Write the nice log header
	$WULogHeader | Out-File -FilePath $WULogFile
 
	# Install: Install selected random updates, append to log, and automatically reboot
	Get-WUInstall -KBArticleID "$WURandomUpdatesWithKB" -AcceptAll -AutoReboot -Verbose | Out-File -FilePath $WULogFile -Append
 
	# Copy Log: Try to copy log file to a network share before automatic reboot
	Copy-Item -Path $WULogFile -Destination $WUNetworkLogPath
}
ELSEIF ($WUMeasuredAllUpdates.Count -gt 0)
{
	# ELSEIF: There must be fewer than X needed random updates, so install all updates (even those without a KB value) if they exist.
 
	# Log Header: Write the nice log header
	$WULogHeader | Out-File -FilePath $WULogFile
 
	# Install: Install all remaining updates, append to log, and automatically reboot
	Get-WUInstall -AcceptAll -AutoReboot -Verbose | Out-File -FilePath $WULogFile -Append
 
	# Copy Log: Try to copy log file to a network share before automatic reboot
	Copy-Item -Path $WULogFile -Destination $WUNetworkLogPath
}
ELSE 
{
	# ELSE: No updates (with or without a KB) are needed
	Exit
}

# Randomize: Get all updates by KB number, randomize, output the defined count, then convert list to comma-delimited string
$WURandomUpdatesByKB = (Get-WUList | Select-Object -Expand KB | Get-Random -Count 3) -join ","
 
# Install: Install random updates and automatically reboot
Get-WUInstall -KBArticleID "$WURandomUpdatesByKB" -AcceptAll -AutoReboot -Verbose