There is a bug in the Server Clock Drift (Powershell) - Clock Drift NTP component. If you make the following changes it should work reliably, I think.
Starting around line 24...
=====
If ($remoteToSolarSkew)
{
$Skew = $remoteToSolarSkew.TotalSeconds - $ntpToSolarSkew;
$stat=[math]::round($Skew,2);
#$symb=$Skew.ToString().Substring(0,1);
$symb=$stat.ToString().Substring(0,1);
if ($symb -eq "-")
{
#$stat=[math]::round($Skew,2);
$tmp=$stat.ToString().Remove(0,1);
Write-Host "Message: Clock drift: $stat.";
Write-Host "Statistic: $tmp";
exit 0;
}
else
{
$stat=[math]::round($Skew,2);
#Write-Host "Message: Clock drift: $symb $stat s.";
Write-Host "Message: Clock drift: $stat s.";
Write-Host "Statistic: $stat";
exit 0;
}
}
=====
aLTeReGo - not sure if you can validate whether this error exists in the version on thwack. The version that ships with SAM 6.1.1 has the error it. By way of explanation, the error is that calling ::round() on a number like -0.00121 will be rounded to 0.00 (notice the negative sign was dropped). But the $symb is set prior to rounding, so the logic for removing the negative symbol is used on a string with no negative symbol, which then results in $stat printing an empty string instead of a 0.