Storage-account-policy-monitor.json

{
  "properties": {
    "displayName": "storage-capacity-alert",
    "policyType": "Custom",
    "mode": "All",
    "parameters": {
      "metricName": {
        "type": "String",
        "metadata": {
          "displayName": "Metric name",
          "description": "The metric name that an alert rule nabmust be eled on. See https://docs.microsoft.com/en-us/azure/monitoring-and-diagnostics/monitoring-supported-metrics#microsoftbatchbatchaccounts for a list of metrics."
        },
        "defaultValue": "Transactions"
      }
    },
    "policyRule": {
      "if": {
        "allOf": [
          {
            "field": "type",
            "equals": "Microsoft.Storage/storageAccounts"
          },
          {
            "field": "kind",
            "equals": "FileStorage"
          },
          {
            "field": "Microsoft.Storage/storageAccounts/sku.tier",
            "equals": "Premium"
          }
        ]
      },
      "then": {
        "effect": "AuditIfNotExists",
        "details": {
          "type": "Microsoft.Insights/metricAlerts",
          "existenceScope": "Subscription",
          "existenceCondition": {
            "allOf": [
              {
                "field": "Microsoft.Insights/metricalerts/enabled",
                "equals": "true"
              },
              {
                "field": "Microsoft.Insights/metricAlerts/criteria.Microsoft.Azure.Monitor.MultipleResourceMultipleMetricCriteria.allOf[*].metricName",
                "equals": "[parameters('metricName')]"
              },
              {
                "field": "Microsoft.Insights/metricalerts/scopes[*]",
                "equals": "[concat('/subscriptions/', subscription().subscriptionId, '/resourceGroups/', resourceGroup().name, '/providers/Microsoft.Storage/storageAccounts/', field('name'))]"
              }
            ]
          }
        }
      }
    }
  },
  "id": "/subscriptions/7d91561b-788f-465e-81aa-39409f1f6b3a/providers/Microsoft.Authorization/policyDefinitions/f9a14599-96d8-417f-b206-84e030dcd7df",
  "type": "Microsoft.Authorization/policyDefinitions",
  "name": "f9a14599-96d8-417f-b206-84e030dcd7df",
}