How to use powershell to wait for an action to complete - azure

Question

I have a script to start VMs/Stop them at a specific time. The issue is, I want the script to only exit when all the VMs are started/running or when they are deallocated/stopped. My current problem is when a VM is starting, it waits until it has started before moving to the next one.
eg: vm1 is starting..
vm2 is starting..
vm3 is starting..
vm1 is now running..
vm2 is still starting
vm3 is still starting
vm1 is now running..
vm2 is now running..
vm3 is now running..
Then script exits.
Full script here
$ACTION="start"
Write-Output "Number of Virtual Machines: $($GetVMS.Name.Count)" `n
$GetVMS | Format-Table
$startstopvm = {
$ResourceGroupName = $args[0]
$Name = $args[1]
$ACTION = $args[2]
# Get VM status
try {
$VMs = Get-AzureRmVM -Name $Name -ResourceGroupName $ResourceGroupName -Status -WarningAction SilentlyContinue
} catch {
Write-Output ("Cloud not get vm $Name in $ResourceGroupName")
$Error[0]
Exit 1
}
if ($ACTION -eq "start")
{
foreach ($VM in $VMs)
{
if ($VM.Statuses[1].Code -eq "PowerState/running")
{
Write-Output ($VM.Name + " in " + $VM.ResourceGroupName + " is already running")
}
else
{
# The VM needs to be started
Write-Output ("Starting VM " + $VM.Name)
$startVM += Start-AzureRmVM -Name $VM.Name -ResourceGroupName $VM.ResourceGroupName -AsJob -ErrorAction Continue
$startTime = Get-Date
$timeElapsed = $((Get-Date) - $startTime).TotalMinutes
while ($timeElapsed -lt 2)
{
$startVM = Get-AzureRmVM -Name $VM.Name -ResourceGroupName $VM.ResourceGroupName -Status -WarningAction SilentlyContinue
if ($startVM.Statuses[1].Code -match "PowerState/(running|starting)")
{
# The VM started, so send notice
Write-Output ($VM.Name + " in " + $VM.ResourceGroupName + " has been started`n")
break
}
Start-Sleep -s 30
}
if ($getStat.Statuses[1].Code -ne "PowerState/(running|starting)")
{
# The VM failed to start, so send notice
Write-Output ($VM.Name + " failed to start`n")
}
}
}
}
NOTE: I am reading the VM name & RG from a file
try {
$VMList = Get-Content C:\Users\local\Desktop\VMs.csv | ConvertFrom-Csv
} catch {
Write-Output ("Cannot open file...")
exit -1
}
$Result = #()
foreach ($vm in $VMList) {
Invoke-Command -ArgumentList $vm.ResourceGroupName, $vm.Name, $ACTION -Verbose -ScriptBlock $startstopvm
}

Answer 1

The simplest way I have done this in the past is to use the -Wait parameter on a Start-Process cmdlet.
You should be able to implement this with small changes.
Saving your current code block into a seperate .ps1 i.e. startstopvm.ps1
You could then change the Invoke-Commmand line to read something like:
Invoke-Command -ArgumentList $vm.ResourceGroupName, $vm.Name, $ACTION -Verbose -ScriptBlock {Start-Process powershell.exe -Argument "C:\Scripts\Backup.ps1 TestBackup" -Wait}
Definitely some other ways to do it but an approach like this has always worked for me