Trigger Specification

This specification describes the azure-monitor trigger that scales based on an Azure Monitor metric.

triggers:
- type: azure-monitor
  metadata:
    resourceURI: Microsoft.ContainerService/managedClusters/azureMonitorCluster
    tenantId: xxx-xxx-xxx-xxx-xxx
    subscriptionId: yyy-yyy-yyy-yyy-yyy
    resourceGroupName: azureMonitor
    metricName: kube_pod_status_ready
    metricFilter: namespace eq 'default'
    metricAggregationInterval: "0:1:0"
    targetValue: "1"
    activeDirectoryClientId: <client id value> # Optional, can use TriggerAuthentication as well
    activeDirectoryClientIdFromEnv: CLIENT_ID_ENV_NAME # Optional, can use TriggerAuthentication as well
    activeDirectoryClientPasswordFromEnv: CLIENT_PASSWORD_ENV_NAME # Optional, can use TriggerAuthentication as well

Parameter list:

• resourceURI - Shortened URI to the Azure resource with format "<resourceProviderNamespace>/<resourceType>/<resourceName>".
• tenantId - Id of the tenant that contains the Azure resource. This is used for authentication.
• subscriptionId - Id of Azure subscription that contains the Azure resource. This is used for determining the full resource URI.
• resourceGroupName - Name of the resource group for the Azure resource.
• metricName - Name of the metric which can be found in the official documentation.
• targetValue - Target value to trigger scaling actions.
• metricAggregationType - Aggregation method of the Azure Monitor metric. Optionsinclude Average, Total, Maximum with a full list in the official documentation.
• metricFilter - Name of the filter to be more specific by using dimensions listed in the official documentation. (optional)
• metricAggregationInterval - Collection time of the metric in format "hh:mm:ss" (default: "0:5:0" which is 5 minutes)
• activeDirectoryClientId - Id of the Active Directory application which requires at least Monitoring Reader permissions. Optional. Required when TriggerAuthentication is not provided.
• activeDirectoryClientPasswordFromEnv - Name of the environment variable that contains the active directory client password.Optional. Required when TriggerAuthentication is not provided.

Some parameters could be provided using environmental variables, instead of setting them directly in metadata. Here is a list of parameters you can use to retrieve values from environment variables:

• activeDirectoryClientIdFromEnv - Id of the Active Directory application which requires at least Monitoring Reader permissions, similar to activeDirectoryClientId, but reads it from an environment variable on the scale target. Optional. Required when TriggerAuthentication is not provided.

Authentication Parameters

You can use TriggerAuthentication CRD to configure the authentication by providing a set of Azure Active Directory credentials or by using pod identity.

Credential based authentication:

• activeDirectoryClientId - Id of the Active Directory application which requires at least Monitoring Reader permissions
• activeDirectoryClientPassword - Password of the Active Directory application

The user will need access to read data from the Azure resource.

Example

apiVersion: v1
kind: Secret
metadata:
  name: azure-monitor-secrets
data:
  activeDirectoryClientId: <clientId>
  activeDirectoryClientPassword: <clientPassword>
---
apiVersion: keda.sh/v1alpha1
kind: TriggerAuthentication
metadata:
  name: azure-monitor-trigger-auth
spec:
  secretTargetRef:
    - parameter: activeDirectoryClientId
      name: azure-monitor-secrets
      key: activeDirectoryClientId
    - parameter: activeDirectoryClientPassword
      name: azure-monitor-secrets
      key: activeDirectoryClientPassword
  # or Pod Identity, kind: Secret is not required in case of pod Identity
  podIdentity:
      provider: azure
---
apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
  name: azure-monitor-scaler
spec:
  scaleTargetRef:
    name: azure-monitor-example
  minReplicaCount: 1
  maxReplicaCount: 10
  triggers:
  - type: azure-monitor
    metadata:
      resourceURI: Microsoft.ContainerService/managedClusters/azureMonitorCluster
      tenantId: xxx-xxx-xxx-xxx-xxx
      subscriptionId: yyy-yyy-yyy-yyy-yyy
      resourceGroupName: azureMonitor
      metricName: kube_pod_status_ready
      metricFilter: namespace eq 'default'
      metricAggregationInterval: "0:1:0"
      metricAggregationType: Average
      targetValue: "1"
    authenticationRef:
      name: azure-monitor-trigger-auth

Currently available scalers for KEDA