#Requires -Version 5.1
<#
    JbTecWiz Support Centre -- generated fix script

    Fault : Time is wrong across the domain -- w32time events 129, 36, 47
    Fix   : Point the PDC emulator at a real external source
    Source: https://jbtecwiz.com/support/srv-time-w32time

    Run as     : Elevated PowerShell on the PDC emulator
    Expect     : 25 minutes
    Risk       : medium
    Reversible : yes

    WHEN THIS IS THE RIGHT FIX
    The whole domain's time comes from this one machine, so this is where to
    start.

    HOW TO UNDO IT
    w32tm /config /syncfromflags:domhier /update returns it to domain
    hierarchy, then restart w32time.

    This script walks the fix one step at a time and asks before each
    one. Steps with no command are things you do yourself -- it prints
    those and waits. Run with -DryRun to print without executing.

    --------------------------------------------------------------------
    NO WARRANTY - USE AT YOUR OWN RISK

    This script is provided by JbTecWiz as-is and with no warranty of any
    kind, express or implied. You run it entirely at your own risk.

    JbTecWiz accepts no liability for any loss or damage arising from its
    use, including but not limited to data loss, downtime, or configuration
    changes that turn out to be wrong for your system.

    You are responsible for reading this script before running it, for
    satisfying yourself that it suits the machine in front of you, and for
    having a working backup first. Some steps cannot be undone.
    --------------------------------------------------------------------
#>

[CmdletBinding()]
param(
    # Print every step and command without running anything.
    [switch]$DryRun,
    # Do not ask before each step. Read the script first if you use this.
    [switch]$Unattended
)

$ErrorActionPreference = 'Stop'
$script:Failed = 0

function Write-Rule { param([string]$Text)
    Write-Host ''
    Write-Host ('-' * 70) -ForegroundColor DarkGray
    if ($Text) { Write-Host $Text -ForegroundColor Cyan }
}

function Show-Prose { param([string]$Text, [string]$Colour = "Gray")
    if (-not $Text) { return }
    $words = $Text -split "\s+"; $line = "  "
    foreach ($w in $words) {
        if (($line.Length + $w.Length) -gt 74) { Write-Host $line -ForegroundColor $Colour; $line = "  " }
        $line += "$w "
    }
    if ($line.Trim()) { Write-Host $line -ForegroundColor $Colour }
}

function Invoke-Step {
    param(
        [int]$Number, [string]$Do, [string]$Why,
        [scriptblock]$Command, [switch]$Manual, [string]$Shell = "powershell"
    )
    Write-Rule "  Step $Number of 6"
    Show-Prose $Do "White"
    if ($Why) { Write-Host ""; Show-Prose $Why "DarkGray" }

    if ($Manual) {
        Write-Host ''
        Write-Host '  -> Do this yourself, then press Enter to carry on.' -ForegroundColor Yellow
        if (-not $Unattended -and -not $DryRun) { [void](Read-Host) }
        return
    }

    Write-Host ''
    foreach ($l in ($Command.ToString().Trim() -split "`n")) {
        Write-Host ("    " + $l.Trim()) -ForegroundColor Green
    }
    Write-Host ''

    if ($DryRun) { Write-Host "  (dry run -- not executed)" -ForegroundColor DarkGray; return }
    if (-not $Unattended) {
        $a = Read-Host "  Run this step? [Y]es / [S]kip / [Q]uit"
        if ($a -match "^[Qq]") { Write-Host "  Stopped at your request."; exit 0 }
        if ($a -match "^[Ss]") { Write-Host "  Skipped." -ForegroundColor DarkGray; return }
    }
    try { & $Command }
    catch {
        $script:Failed++
        Write-Host ("  Step $Number failed: " + $_.Exception.Message) -ForegroundColor Red
        Show-Prose "The rest of the fix may depend on this. Read the write-up before carrying on." "Red"
        if (-not $Unattended) {
            $c = Read-Host "  Carry on anyway? [y/N]"
            if ($c -notmatch "^[Yy]") { exit 1 }
        }
    }
}

Write-Rule
Write-Host '  Time is wrong across the domain -- w32time events 129, 36, 47' -ForegroundColor White
Write-Host '  Point the PDC emulator at a real external source' -ForegroundColor Cyan
Write-Host ''
Write-Host '  Risk: medium   Reversible   25 minutes'
Write-Host ''
Show-Prose 'No warranty. Use at your own risk - JbTecWiz accepts no liability. Read it before you run it, and have a backup.' 'DarkYellow'
Write-Rule

if (-not $Unattended -and -not $DryRun) {
    $go = Read-Host '  Ready? [y/N]'
    if ($go -notmatch "^[Yy]") { Write-Host "  Nothing was changed."; exit 0 }
}

Invoke-Step -Number 1 -Do 'Confirm which DC actually holds the role.' -Command {
    Get-ADDomain | Select-Object PDCEmulator
}

Invoke-Step -Number 2 -Do 'Look at the current configuration and source.' -Command {
    w32tm /query /status /verbose
    w32tm /query /configuration
}

Invoke-Step -Number 3 -Do 'Configure it to take time from external NTP servers.' -Why '0x8 means send as a client in normal mode. /reliable:yes marks this machine as the authority the rest of the domain trusts.' -Command {
    cmd.exe /c 'w32tm /config /manualpeerlist:"time.windows.com,0x8 uk.pool.ntp.org,0x8" /syncfromflags:manual /reliable:yes /update'
}

Invoke-Step -Number 4 -Do 'Restart the service and force a resync.' -Command {
    cmd.exe /c 'Restart-Service w32time & w32tm /resync /rediscover'
}

Invoke-Step -Number 5 -Do 'If the DC is a Hyper-V guest, disable the host time synchronisation integration service -- two authorities fight and neither wins.' -Why 'Run this on the Hyper-V host. A virtualised PDC taking time from both its host and NTP oscillates, and the resulting skew is intermittent and maddening to trace.' -Command {
    Disable-VMIntegrationService -VMName DC01 -Name 'Time Synchronization'
}

Invoke-Step -Number 6 -Do 'Check the outbound path -- UDP 123 has to be open to the internet or to an internal appliance.' -Command {
    Test-NetConnection -ComputerName uk.pool.ntp.org -Port 123 -InformationLevel Detailed
}

Write-Rule "  Confirm it worked"
Show-Prose 'The source is the external server and the offset is small.' 'White'
Write-Host ''
if (-not $DryRun) {
    cmd.exe /c 'w32tm /query /source & w32tm /query /status | findstr /i "offset source stratum"'
}

Write-Rule
if ($script:Failed -gt 0) {
    Write-Host ("  Finished with " + $script:Failed + " failed step(s).") -ForegroundColor Yellow
    Show-Prose 'Read the full write-up at https://jbtecwiz.com/support/srv-time-w32time' 'Yellow'
} else {
    Write-Host '  Finished.' -ForegroundColor Green
}
Write-Host ''
Show-Prose 'To undo: w32tm /config /syncfromflags:domhier /update returns it to domain hierarchy, then restart w32time.' 'DarkGray'
Write-Rule