Start / stop VMs on a schedule

Create an Azure function application and deploy functions that starts or stops virtual machines in the specified resource group, subscription, or by tag on a schedule.

Login to Azure Account

Install-Module -Name Az -AllowClobber -Scope AllUsers

Connect-AzAccount
$subcription = Get-AzSubscription
$subcription
Select-AzSubscription -Tenant <{TenantId}>

Create a new resource group and function application on Azure

Publish ARM template

Go to Templates in Azure portal and copy azuredeploy.json to newly created template.

Deploy ARM template

Modify the values for each of the below variables in run.ps1 as needed.

# Specify the VMs that you want to stop. Modify or comment out below based on which VMs to check.
#$VMResourceGroupName = "vmrg"
#$VMName = "testVM1"
$TagName = "AutomaticallyStart"

Modify the start and stop time in the function.json file. They are currently set to 6:30am and 6:30pm CEST. You can change the timezone by modifying the application setting WEBSITE_TIME_ZONE. You can also pass in a parameter 'timezone' to the above [ARM template] that was used to create the function application if you want a different timezone so that daylight savings time will be honored.

{
  "disabled": false,
  "bindings": [
    {
      "name": "Timer",
      "type": "timerTrigger",
      "direction": "in",
      "schedule": "0 0 20 * * *"
    }
  ]
}

Go to template newly created, click on Deploy Provide the name of new resource group where this template will be deployed Click on Publish

This should create a new resource group with a function application and a managed service identity enabled. The id of the service principal for the MSI should be returned as an output from the deployment.

Example: principalId String cac1fa06-2ad8-437d-99f6-b75edaae2921

Grant the managed service identity contributor access to the subscription or resource group so it can perform actions

The below command sets the access at the subscription level.

$Context = Get-AzContext
New-AzRoleAssignment -ObjectId <principalId> -RoleDefinitionName Contributor -Scope "/subscriptions/$($Context.Subscription)"