Azure Autoscale

This Terraform module manage autoscaling configuration on a given Azure resource.

This module comes with a default profile working with Virtual Machine Scale Sets and App Service Plans based on Azure Monitor CPU and memory metrics. Also, this module allows to override it with custom profiles and rules.

Global versioning rule for Claranet Azure modules

Module version	Terraform version	OpenTofu version	AzureRM version
>= 8.x.x	Unverified	1.8.x	>= 4.0
>= 7.x.x	1.3.x		>= 3.0
>= 6.x.x	1.x		>= 3.0
>= 5.x.x	0.15.x		>= 2.0
>= 4.x.x	0.13.x / 0.14.x		>= 2.0
>= 3.x.x	0.12.x		>= 2.0
>= 2.x.x	0.12.x		< 2.0
< 2.x.x	0.11.x		< 2.0

Contributing

If you want to contribute to this repository, feel free to use our pre-commit git hook configuration which will help you automatically update and format some files for you by enforcing our Terraform code module best-practices.

More details are available in the CONTRIBUTING.md file.

Usage

This module is optimized to work with the Claranet terraform-wrapper tool which set some terraform variables in the environment needed by this module. More details about variables set by the terraform-wrapper available in the documentation.

⚠️ Since modules version v8.0.0, we do not maintain/check anymore the compatibility with Hashicorp Terraform. Instead, we recommend to use OpenTofu.

module "linux_scaleset" {
  source  = "claranet/linux-scaleset/azurerm"
  version = "x.x.x"

  client_name    = var.client_name
  environment    = var.environment
  stack          = var.stack
  location       = module.azure_region.location
  location_short = module.azure_region.location_short

  resource_group_name = module.rg.name

  admin_username = "myusername"
  ssh_public_key = var.ssh_public_key

  vm_size = "Standard_B2s"

  subnet = {
    id = module.subnet.id
  }

  source_image_reference = {
    publisher = "Debian"
    offer     = "debian-10"
    sku       = "10"
    version   = "latest"
  }

  azure_monitor_data_collection_rule = {
    id = module.run.data_collection_rule_id
  }

  identity = {
    type = "SystemAssigned"
  }
}

module "autoscale" {
  source  = "claranet/autoscale/azurerm"
  version = "x.x.x"

  client_name         = var.client_name
  environment         = var.environment
  stack               = var.stack
  location            = module.azure_region.location
  location_short      = module.azure_region.location_short
  resource_group_name = module.rg.name

  target_resource_id = module.linux_scaleset.id

  profile = {
    "default" = {
      capacity = {
        default = 2
        minimum = 2
        maximum = 5
      }
      rules = [
        {
          metric_trigger = {
            metric_name        = "Percentage CPU"
            metric_resource_id = module.linux_scaleset.id
            time_grain         = "PT1M"
            time_window        = "PT5M"
            time_aggregation   = "Average"
            statistic          = "Average"
            operator           = "GreaterThanOrEqual"
            threshold          = 75
            metric_namespace   = "microsoft.compute/virtualmachinescalesets"
          }

          scale_action = {
            direction = "Increase"
            type      = "ChangeCount"
            value     = "1"
            cooldown  = "PT1M"
          }
        },
        {
          metric_trigger = {
            metric_name        = "Percentage CPU"
            metric_resource_id = module.linux_scaleset.id
            time_grain         = "PT1M"
            time_window        = "PT5M"
            time_aggregation   = "Average"
            statistic          = "Average"
            operator           = "LessThan"
            threshold          = 25
            metric_namespace   = "microsoft.compute/virtualmachinescalesets"
          }

          scale_action = {
            direction = "Decrease"
            type      = "ChangeCount"
            value     = "1"
            cooldown  = "PT1M"
          }
        }
      ]
    }
  }

  notification = {
    email = {
      custom_emails = ["[email protected]"]
    }
  }

  logs_destinations_ids = [module.run.log_analytics_workspace_id]
}

Providers

Name	Version
azurecaf	~> 1.2.28
azurerm	~> 4.0

Modules

Name	Source	Version
diagnostics	claranet/diagnostic-settings/azurerm	~> 8.0.0

Resources

Name	Type
azurerm_monitor_autoscale_setting.main	resource
azurecaf_name.autoscale	data source

Inputs

Name	Description	Type	Default	Required
autoscale_enabled	Specifies whether automatic scaling is enabled for the target resource.	bool	true	no
client_name	Client name/account used in naming.	string	n/a	yes
custom_name	Custom name for Autoscale setting, generated if not set.	string	""	no
default_tags_enabled	Option to enable or disable default tags.	bool	true	no
diagnostic_settings_custom_name	Custom name of the diagnostics settings, name will be 'default' if not set.	string	"default"	no
environment	Project environment.	string	n/a	yes
extra_tags	Additional tags to associate with your autoscale setting.	map(string)	{}	no
location	Azure location/region to use.	string	n/a	yes
location_short	Short string for Azure location.	string	n/a	yes
logs_categories	Log categories to send to destinations.	list(string)	null	no
logs_destinations_ids	List of destination resources IDs for logs diagnostic destination. Can be Storage Account, Log Analytics Workspace and Event Hub. No more than one of each can be set. If you want to use Azure EventHub as a destination, you must provide a formatted string containing both the EventHub Namespace authorization send ID and the EventHub name (name of the queue to use in the Namespace) separated by the | character.	list(string)	n/a	yes
logs_metrics_categories	Metrics categories to send to destinations.	list(string)	null	no
name_prefix	Optional prefix for the generated name.	string	""	no
name_suffix	Optional suffix for the generated name.	string	""	no
notification	Manage emailing and webhooks for sending notifications.	object({ email = optional(object({ send_to_subscription_administrator = optional(bool, false) send_to_subscription_co_administrator = optional(bool, false) custom_emails = optional(list(string)) })) webhooks = optional(list(object({ service_uri = string properties = optional(map(string)) })), []) })	null	no
profile	One or more (up to 20) autoscale profile blocks.	map(object({ capacity = object({ default = number minimum = optional(number, 1) maximum = optional(number, 5) }) rules = optional(list(object({ metric_trigger = object({ metric_name = string metric_resource_id = string operator = string statistic = string time_aggregation = string time_grain = string time_window = string threshold = number metric_namespace = optional(string) divide_by_instance_count = optional(bool) dimensions = optional(list(object({ name = string operator = string values = list(string) })), []) }) scale_action = object({ cooldown = string direction = string type = string value = number }) })), []) fixed_date = optional(object({ end = string start = string timezone = string })) recurrence = optional(object({ timezone = string days = list(string) hours = list(number) minutes = list(number) })) }))	n/a	yes
resource_group_name	Custom resource group name to attach autoscale configuration to. Target resource group by default.	string	null	no
stack	Project stack name.	string	n/a	yes
target_resource_id	ID of the resource to apply the autoscale setting to.	string	n/a	yes

Outputs

Name	Description
id	ID of the Azure Autoscale setting.
module_diagnostics	Diagnostics Settings module output.
name	Name of the Azure Autoscale setting.
resource	Azure Autoscale setting resource object.

Related documentation

Microsoft Azure documentation - Virtual Machine Scale Sets Autoscale: docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-autoscale-overview

Microsoft Azure documentation - App Services Autoscale: docs.microsoft.com/en-us/azure/app-service/manage-scale-up

Microsoft Azure documentation - Metrics supported: docs.microsoft.com/en-us/azure/azure-monitor/essentials/metrics-supported