问题描述
使用Azure Policy服务，对公司内部全部的订阅下的Activity Log，都需要配置导出到Log A Workspace中。
以下Policy规则可以实现此目的。
Policy内容说明
在Policy Rule部分中，选择资源的类型为 "Microsoft.Resources/subscriptions"， 效果使用 DeployIfNotExists (如果不存在，则通过修复任务进行修正。
在 existenceCondition 条件中，如果当前订阅已经启用了 diagnostic setting并且输出日志到同一个Log A workspace，表示满足Policy要求，不需要进行修正。
在 deployment 中，使用了 ARM 模板， 为订阅添加Diagnostic Setting并且所有的日志Category均启用。
因 deployment 操作，会修改诊断日志配置(属于Monitor服务)以及Log A Workspace，所以需要为这个ARM Deployment操作给与两个contributor权限， 即 roleDefinitionIds 中的内容。
使用三个输入参数 logAnalytics， effect， logsEnabled 作为Policy的判断条件。
Policy示例
{"mode": "All","policyRule": {"if": {"field": "type","equals": "Microsoft.Resources/subscriptions"},"then": {"effect": "[parameters('effect')]","details": {"type": "Microsoft.Insights/diagnosticSettings","deploymentScope": "subscription","existenceScope": "subscription","existenceCondition": {"allOf": [{"field": "Microsoft.Insights/diagnosticSettings/logs.enabled","equals": "[parameters('logsEnabled')]"},{"field": "Microsoft.Insights/diagnosticSettings/workspaceId","equals": "[parameters('logAnalytics')]"}]},"deployment": {"location": "chinaeast2","properties": {"mode": "incremental","template": {"$schema": "https://schema.management.azure.com/schemas/2018-05-01/subscriptionDeploymentTemplate.json#","contentVersion": "1.0.0.0","parameters": {"logAnalytics": {"type": "string"},"logsEnabled": {"type": "string"}},"variables": {},"resources": [{"name": "policy-enabled-ActivityLogs-to-logA","type": "Microsoft.Insights/diagnosticSettings","apiVersion": "2017-05-01-preview","location": "Global","properties": {"workspaceId": "[parameters('logAnalytics')]","logs": [{"category": "Administrative","enabled": "[parameters('logsEnabled')]"},{"category": "Security","enabled": "[parameters('logsEnabled')]"},{"category": "ServiceHealth","enabled": "[parameters('logsEnabled')]"},{"category": "Alert","enabled": "[parameters('logsEnabled')]"},{"category": "Recommendation","enabled": "[parameters('logsEnabled')]"},{"category": "Policy","enabled": "[parameters('logsEnabled')]"},{"category": "Autoscale","enabled": "[parameters('logsEnabled')]"},{"category": "ResourceHealth","enabled": "[parameters('logsEnabled')]"}]}}],"outputs": {}},"parameters": {"logAnalytics": {"value": "[parameters('logAnalytics')]"},"logsEnabled": {"value": "[parameters('logsEnabled')]"}}}},"roleDefinitionIds": ["/providers/microsoft.authorization/roleDefinitions/749f88d5-cbae-40b8-bcfc-e573ddc772fa","/providers/microsoft.authorization/roleDefinitions/92aaf0da-9dab-42b6-94a3-d43ce8d16293"]}}},"parameters": {"logAnalytics": {"type": "String","metadata": {"displayName": "Primary Log Analytics workspace","description": "If this workspace is outside of the scope of the assignment you must manually grant 'Log Analytics Contributor' permissions (or similar) to the policy assignment's principal ID.","strongType": "omsWorkspace","assignPermissions": true}},"effect": {"type": "String","metadata": {"displayName": "Effect","description": "Enable or disable the execution of the policy"},"allowedValues": ["DeployIfNotExists","Disabled"],"defaultValue": "DeployIfNotExists"},"logsEnabled": {"type": "String","metadata": {"displayName": "Enable logs","description": "Whether to enable logs stream to the Log Analytics workspace - True or False"},"allowedValues": ["True","False"],"defaultValue": "True"}} }
