Script for Azure Backup notifications

Question

I's just a basic one, I am new to Powershell. Trying to get the statement below working.

$date = (Get-Date).AddDays(-1)

$currentdate = Get-Date -Format d

$check = Get-WinEvent -FilterHashtable @{LogName="CloudBackup";StartTime=$date;ID=3} *>$null

if ($check -eq $true) {
  Write-Host "`nOK: Azure Backup was successful on $currentdate"
  exit 0
} else {
  Write-Host "`nCritical: Problem with Azure Backup - $currentdate"
  exit 2
}

Specially if ($check -eq $true) doesn't seem to do what expected. As $check is checking for event ID 3 in the eventlog, if it's there it should return true, if not false. Unfortunately it's returning only false every time.

Could someone please advise? Is there a better way to do that?

Answer 1

$check = Get-WinEvent ... *>$null

Your redirection is suppressing all output, so $check always has the value $null, which is interpreted as $false in a boolean operation.

What you want to use is the automatic variable $? to check it if the last PowerShell operation was successful.

if ($?) {
  Write-Host "OK: Azure Backup was successful on $currentdate"
  exit 0
} else {
  Write-Host "Critical: Problem with Azure Backup - $currentdate"
  exit 2
}