2025-08-23 - quickie - scheduled storage vmotions using powercli

Gluing bits together.

Got asked to do this at work the other day, and was struggling to find a good resource that combined all the elements into one place - and a lot of stuff had the wrong idea of trying to create a scheduled task on a Windows guest rather than using scheduled tasks applied to the VM. Hopefully this helps someone, given just how much of this is boilerplate!

#PowerShell

#region variables

# For the script at work, these variables are passed in by other automation 
# systems, but are hardcoded in this example script.

$targetdate = "2026-01-01"
$engineer = "Your Name Here"
$email = "asdf@example.com"
$vm = "EXAMPLE-VM01"
# must be FQDN
$vcentre = "yourvcentrehere.example.com"
$targetdatastore = "DATASTORE-02"
# These IDs are examples, get using Get-VM $vm | Get-HardDisk
$targetdisks_string = "2003,2014"
$migrateconfigfile = "Y"

#endregion

# Connect to VCentre - you may need to provide credentials depending on settings
Connect-VIServer $vcentre

#region gather info

$targetdatastore_ref = (Get-Datastore $targetdatastore | Get-View).MoRef

$vm_details = Get-VM $vm
$vm_view = Get-View $vm_details
$alldisks = $vm_details | Get-HardDisk
$targetdisks = $targetdisks_string.split(",").Trim()

#endregion

#region relocate initial setup
$relocate_spec = New-Object VMware.Vim.VirtualMachineRelocateSpec

if ($migrateconfigfile -like "Y*") {
    $relocate_spec.datastore = $targetdatastore_ref
}

#endregion

#region disks
$disk_int = 0

if ($targetdisks) {
    # these need to be created at the same time,
    # before the disks are addressed separately
    $relocate_spec.Disk = $targetdisks | ForEach-Object {
        New-Object VMware.Vim.VirtualMachineRelocateSpecDiskLocator
    }
}

foreach ($disk_id in $targetdisks) {
    $disk_check = $alldisks | Where-Object Id -like "*/$disk_id"
    if ($null -eq $disk_check) {
        throw "$disk_id not found for VM $vm"
    }

    $relocate_spec.Disk[$disk_int].DiskId = $disk_id
    $relocate_spec.Disk[$disk_int].Datastore = $targetdatastore_ref

    Clear-Variable disk_check 
    $disk_int++
}

#endregion

#region scheduled task

$task_spec = New-Object VMware.Vim.ScheduledTaskSpec
# this might need adjusting since there's a fairly low character limit
$task_spec.Name = "$engineer - $vm Storage $((Get-Date).ToShortDateString())"
$task_spec.Description = "Storage migration created via PowerShell on $(Get-Date)"
$task_spec.Enabled = $true
$task_spec.Notification = $email

$task_spec.Scheduler = New-Object VMware.Vim.OnceTaskScheduler
# The task scheduler runs based on UTC.
$task_spec.Scheduler.RunAt = (Get-Date $targetdate).ToUniversalTime()

$task_spec.Action.Name = "RelocateVM_Task"
$task_spec.Action.Argument = New-Object VMware.Vim.MethodActionArgument
$task_spec.Action.Argument[0].Value = $relocate_spec

$TaskManager = Get-View ScheduledTaskManager
$TaskManager.CreateScheduledTask($vm_view.MoRef, $task_spec)

#endregion