This script gets the Active Directory server uptime in days using WMI. The WMI class used is Win32_OperatingSystem

I have used the New-Timespan to calculate the uptime (difference between the current date and the last Windows boot up time).

[TimeSpan]$uptime=New-TimeSpan $LBTime $(get-date)
This will compare the output time with the current time and store the result to the string as object

The property ConvertToDateTime gives a readable value contained in the variable “LastBootUpTime”.

The default display of the System.TimeSpan object is shown here:

Days              : 0
Hours             : 0
Minutes           : 40
Seconds           : 55
Milliseconds      : 914
Ticks             : 24559148010
TotalDays         : 0.0284249398263889
TotalHours        : 0.682198555833333
TotalMinutes      : 40.93191335
TotalSeconds      : 2455.914801
TotalMilliseconds : 2455914.801

The script below performs the following actions :

• lists all servers in the Active Directory domain
• ping each server in the list
• if the ping is successful, get the uptime of the server calculated in days

Script :

$list = get-adcomputer -LDAPFilter "(operatingsystem=Windows*Server*)" 

foreach ($entry in $list) {
	$ad_entry = $entry.name
	$strQuery = "select * from win32_pingstatus where address = '" + $ad_entry + "'"
	$wmi = Get-WmiObject -Query $strQuery
	if ($wmi.statuscode -eq 0) {
		try{
			$Booted = Get-WmiObject -Class Win32_OperatingSystem -Computer $ad_entry -ErrorAction Stop -WarningAction Stop
			$uptime = New-TimeSpan -Start $Booted.ConvertToDateTime($Booted.LastBootUpTime) -End (Get-Date)
			$uptime_str = $uptime.Days
			Write-Host $ad_entry ";" $uptime_str
		}
		catch{Write-Host "unable to get uptime info for " $ad_entry}
	}
}

Cmdlet references :

• get-adcomputer
• Get-WmiObject
• New-TimeSpan
• Try/Catch/Finally