NTP, PowerShell, It's about time.

There's no doubt that time is critically important in a computing

environment. Given this sensitivity, and the recent recognition that we

had rogue hosts improperly configured, I decided to crank out a script

that would analyze our environment. I wanted to find whether the NTPD

service was running, what the NTP server configuration was, and provide

a report of this. Additionally I wanted to have the option (with

commenting) to automatically make corrections.

Always open to suggestions and improvements.  I hope this helps you in your environment.

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Connect-VIServer -Server server.domain.com     #Enter your vCenter Server

$NtpServer = "10.10.10.10"   #Provide your default NTP Server. This will be used as default so entering a NTP server when prompted is not necessary

$OldNtpServer = "10.10.10.11"         #Leave set as 127.127.1.0 as default unless you wish to change settings in your environment

$DefaultNtpServer = "127.127.1.0"    #NTP Server Value that is set on a fresh ESX installation.

#Location based on Date

$date = Get-Date -UFormat %Y%m%d

$ExportLocation = "C:\NTP-$date.csv"

#Location where you would like report to be saved to.

#$ExportLocation = 'C:\NTPReport.csv'

$NTPHosts

= Get-VMHost | Select-Object Name,@{Name="NTPServer";Expression={$_ |

Get-VMHostNtpServer}}, @{Name="NTPRunning";Expression={($_ |

Get-VMHostService | Where-Object {$_.key -eq "ntpd"}).Running}} |

Sort-Object -Property "NTPRunning", "NTPServer"

$NTPHosts | Export-Csv $ExportLocation -NoTypeInformation

& $ExportLocation #Opens generated report file

$Restart = Read-Host "Would you like to start NTPD services or change NTP configurations on hosts? (y/n)"

#$Restart = "y"  #Comment above line and uncomment this line if you wish to automatically restart services.

If ($Restart -eq "y"){

Import-Csv $ExportLocation | % {

$vmhost = $_.Name

#Checks the NTP configuration against a value previously determined at the top of script.

If (($_.NTPServer -eq $OldNtpServer) -or ($_.NTPServer -eq $DefaultNtpServer)){

$NtpInput

= Read-Host "Some servers are configured with NTP set as $OldNtpServer

or $DefaultNtpServer and may need their NTP settings reconfigured.

Please enter NTP Server FQDN or IP address. <$NtpServer> is

default."

If ($NtpInput -ne "") {

$NtpServer = $NtpInput

#Sets $NtpServer to the inputted value and does nothign if left blank.

This allows use of default when value is consistent in the environment.

}

Add-VMHostNtpServer -VMHost $vmhost -NtpServer $NtpServer | Where-Object {$_.NTPServer -eq $OldNtpServer}

Remove-VMHostNtpServer -VMHost $vmhost -NtpServer $OldNtpServer

}

#Now time to restart any NTPD services that are currently not running.

If ($_.NTPRunning -eq "False") {

Get-VmHostService -VMHost $vmhost | Where-Object {$_.key -eq "ntpd"} | Start-VMHostService

}

}

}

Write-Host "Process Complete"