workflow StartStopVm
{
    param([string] $RgName, [boolean] $start=$true)

    $Conn = Get-AutomationConnection -Name AzureRunAsConnection
    Add-AzureRMAccount -ServicePrincipal -Tenant $Conn.TenantID -ApplicationID $Conn.ApplicationID -CertificateThumbprint $Conn.CertificateThumbprint
    $vms = Get-AzureRmVM -ResourceGroupName $RgName

    foreach ($vm in $vms){
        if($start){
        Write-Output "Starting $vm.Name"
        Start-AzurermVM -ResourceGroupName $vm.ResourceGroupName -Name $vm.Name

        } else{
        Write-Output "Stopping $vm.Name"
        Stop-AzurermVM -ResourceGroupName $vm.ResourceGroupName -Name $vm.Name -Force
        }
    }
}