Powershell Script - Get-LastBootTime - remotely find out when your servers where last rebooted

Here's another handy and simple function which lets you query a bunch of servers at once to find out when they were last rebooted.  It's taking advantage of Get-WmiObject and the root\civ2\Win32_OperatingSystem class.  For maximum parallelization, I've forced pipeline usage to first colapse the process block into a single array to create only one Get-WmiObject call.  This is significantly faster than the default pipeline behavior which is sequential, with 1000 servers completing under a minute (local LAN) vs sequential calls taking close to 10 minutes.

Here's it in action:

PS C:\> Get-Content .\serverlist.txt | Get-LastBootTime

Name      UpSince
----      -------
NOTSERVER Unknown             
SERVER001 6/20/2015 10:46:25 PM
SERVER002 6/20/2015 10:26:24 PM
SERVER003 6/20/2015 10:30:17 PM
SERVER004 6/20/2015 10:27:52 PM
SERVER005 6/20/2015 10:38:27 PM
SERVER006 6/20/2015 10:30:12 PM
SERVER007 6/20/2015 11:54:01 PM
SERVER008 6/20/2015 10:28:39 PM
SERVER009 6/20/2015 10:26:15 PM
SERVER010 6/20/2015 10:27:01 PM

Source Code: