PowerCLI: A Simple VMware Backup Script

Lately I’ve been doing a lot of work in a lab environment. Some of the work I’m doing is quite important to me so I decided to workout a way I can backup my VM’s onto a backup device. To my surprise this was pretty simple to do.

Here is how I decided the script should function:

1. Send myself an email telling me that the backup process has started
2. Import the name of the VM to be backed up and the destination datastore from a CSV file
3. Create a Snapshot of the VM I want to backup
4. Create a Clone’d VM from the Snapshot
   • Place the backup onto my Backup Datastore
   • Name the backup <master VM name>-<date stamp>
   • Thin provision the backup
5. Remove the Snapshot from the master VM
6. Send myself an email telling me that the backup process has completed

So that’s what I wanted to do, this is what I ended up with.

Backup Script

# Import Backup CSV
$backupinfo =  Import-Csv C:\scripts\mybackups.csv

#Set Date format for clone names
$date = Get-Date -Format "yyyyMMdd"

#Set Date format for emails
$time = (Get-Date -f "HH:MM")

#Connect to vCenter
Connect-VIServer "<vc server>"

foreach ($customer in $backupinfo)
{
	$vm = Get-VM $customer.MasterVM

	#Send Start Email
	C:\scripts\backupstartedemail.ps1

	# Create new snapshot for clone
	$cloneSnap = $vm | New-Snapshot -Name "Clone Snapshot"

	# Get managed object view
	$vmView = $vm | Get-View

	# Get folder managed object reference
	$cloneFolder = $vmView.parent

	# Build clone specification
	$cloneSpec = new-object Vmware.Vim.VirtualMachineCloneSpec
	$cloneSpec.Snapshot = $vmView.Snapshot.CurrentSnapshot

	# Make linked disk specification
	$cloneSpec.Location = new-object Vmware.Vim.VirtualMachineRelocateSpec
	$cloneSpec.Location.Datastore = (Get-Datastore -Name $customer.BackupDS | Get-View).MoRef
	$cloneSpec.Location.Transform =  [Vmware.Vim.VirtualMachineRelocateTransformation]::sparse

	$cloneName = "$vm-$date"

	# Create clone
	$vmView.CloneVM( $cloneFolder, $cloneName, $cloneSpec )

	# Write newly created VM to stdout as confirmation
	Get-VM $cloneName

	# Remove Snapshot created for clone
	Get-Snapshot -VM (Get-VM -Name $customer.MasterVM) -Name $cloneSnap | Remove-Snapshot -confirm:$False

	#Send Complete Email
	C:\scripts\backupcompletedemail.ps1
}
#Disconnect from vCentre
Disconnect-VIServer -Confirm:$false

Send Started Email Script

#Set Date format for emails
$timestart = (Get-Date -f "HH:MM")

$emailFrom = "<senders address>"
$emailTo = "<recipients address>"
$subject = "[$vm - Backup Started]"
$body = "Backup Details
-------------
VM Name:",$vm,"
Clone Name:","$vm-$date","
Target Datastore:", $customer.BackupDS,"
Time Started:", $timestart

$smtpServer = "<smtp server>"
$smtp = new-object Net.Mail.SmtpClient($smtpServer)
$smtp.Send($emailFrom,$emailTo,$subject,$body)

Send Completed Email Script

#Set Date format for emails
$timecomplete = (Get-Date -f "HH:MM")

$emailFrom = "<senders address>"
$emailTo = "<recipients address>"
$subject = "[$vm - Backup Complete]"
$body = "Backup Details
-------------
VM Name:",$vm,"
Clone Name:","$vm-$date","
Target Datastore:", $customer.BackupDS,"
Time Started:", $timestart,"
Time Completed:", $timecomplete
$smtpServer = "<smtp server>"
$smtp = new-object Net.Mail.SmtpClient($smtpServer)
$smtp.Send($emailFrom,$emailTo,$subject,$body)

Content of CSV

The content of the csv file is very simple. This is what mine looks like:

MasterVM,BackupDS
VM1,BackupDataStore
VM2,BackupDataStore

Summary

So as you can see, it’s simple, but very effective. Let me know your thoughts/ideas on this could be improved.

Sources:

• Creating a linked clone from a snapshot point in PowerCli