Change the size of Azure VM in a given schedule using Azure Runbook

In our previous article, I explained how to write a simple PowerShell script to expand the size of an Azure VM.

1. PowerShell script to expand and reduce the size of an Azure VM
2. Change the size of Azure VM in a given schedule using Azure Runbook

In this article I’ll explain how to execute PowerShell scripts in a given schedule using Azure Automation Account, Runbooks and Schedules.

What is an Azure Automation?

Azure Automation is a Software as a Service (SaaS) that can be used to automate processes. You can automate cloud automation tasks using Azure Automation. Some common tasks are,

• Build and deploy resources
• Configure VMs
• Monitor resources

What is a Runbook?

Azure Automation use Runbooks to automate processes. Runbooks are executed in automation Sandboxes, which means as a Platform as a Service (PaaS) VMs. You will get the isolation that you expect from Runbooks

Following are the steps I used to expand and reduce the size of VMs in my Azure tenant.

1. Create Azure Automation Account

Navigate to Variables section and create following variables

2. Create the Runbook

Create new Runbook as a PowerShell script to expand the size

Add following script

$connectionName = "AzureRunAsConnection"

try

{

# Get the connection "AzureRunAsConnection "

$servicePrincipalConnection=Get-AutomationConnection -Name $connectionName

"Logging in to Azure..."

Add-AzureRmAccount `

-ServicePrincipal `

-TenantId $servicePrincipalConnection.TenantId `

-ApplicationId $servicePrincipalConnection.ApplicationId `

-CertificateThumbprint $servicePrincipalConnection.CertificateThumbprint

}

catch {

if (!$servicePrincipalConnection)

{

$ErrorMessage = "Connection $connectionName not found."

throw $ErrorMessage

} else{

Write-Error -Message $_.Exception

throw $_.Exception

}

}

$vmName = Get-AutomationVariable -Name 'vmName'

$resourceGroup = Get-AutomationVariable -Name 'resourceGroup'

$lowHwProfile = Get-AutomationVariable -Name 'lowHwProfile'

"Updating VM size"

Get-AzureRmVMSize -ResourceGroupName $resourceGroup -VMName $vmName

$vm = Get-AzureRmVM -ResourceGroupName $resourceGroup -Name $vmName

$vm.HardwareProfile.VmSize = $lowHwProfile

Update-AzureRmVM -VM $vm -ResourceGroupName $resourceGroup

"VM size updated"

Same way create another Runbook to reduce the VM size

3. Create Schedules and apply to Runbooks

Click on Schedules in Automation Account

Navigate to specific Runbook to apply the schedule

That’s it. We have to create another schedule to reduce the size of the VM on Monday night and apply to the particular Runbook

Presentation - Automating Business Processes with SharePoint & Flow

Following is the presentation I did at Microsoft Student Champs Monthly Meeting- February 2018

PowerShell script to expand and reduce the size of an Azure VM

When we provision VMs from Azure, we select the best possible size template from the gallery. But sometimes our VMs can’t cater the demand for specific time periods or are underutilized in certain times. One of my SQL Server VMs is very busy on Mondays, but manageable on other days.

I had to use Azure PowerShell script to modify the size template. In this article I’ll share the script I’ve used to expand the VM size and later reduce its size.

I’ve split the article in to two

1. PowerShell script to expand and reduce the size of an Azure VM
2. Change the size of Azure VM in a given schedule using Azure Runbook

Expand VM size

$vmName = "Test-VM"
$resourceGroup = "Test-Resource"
$highHwProfile = "Standard_DS13_v2_Promo"
$subscriptionId = "<subscription_id>"

Login-AzureRmAccount
Select-AzureRMSubscription -SubscriptionId $subscriptionId

Get-AzureRmVMSize -ResourceGroupName $resourceGroup -VMName $vmName
$vm = Get-AzureRmVM -ResourceGroupName $resourceGroup -Name $vmName
$vm.HardwareProfile.VmSize = $highHwProfile
Update-AzureRmVM -VM $vm -ResourceGroupName $resourceGroup

Reduce VM size

$vmName = "Test-VM"
$resourceGroup = "Test-Resource"
$highHwProfile = "Standard_DS12_v2_Promo"
$subscriptionId = "<subscription_id>"

Login-AzureRmAccount
Select-AzureRMSubscription -SubscriptionId $subscriptionId

Get-AzureRmVMSize -ResourceGroupName $resourceGroup -VMName $vmName
$vm = Get-AzureRmVM -ResourceGroupName $resourceGroup -Name $vmName
$vm.HardwareProfile.VmSize = $highHwProfile
Update-AzureRmVM -VM $vm -ResourceGroupName $resourceGroup