Missing Domain Controller Heartbeat

let query_frequency = 15m;
let missing_period = 1h;
//Enter a reference list of hostnames for your DC servers
let DCServersList = dynamic (["DC01.simulandlabs.com","DC02.simulandlabs.com"]);
//Alternatively, a Watchlist can be used
//let DCServersList = _GetWatchlist('HostName-DomainControllers') | project HostName;
Heartbeat
| summarize arg_max(TimeGenerated, *) by Computer
| where Computer in (DCServersList)
//You may specify the OS type of your Domain Controllers
//| where OSType == 'Windows'
| where TimeGenerated between (ago(query_frequency + missing_period) .. ago(missing_period))
| project TimeGenerated, Computer, OSType, Version, ComputerEnvironment, Type, Solutions
| sort by TimeGenerated asc

severity: High
queryFrequency: 15m
kind: Scheduled
version: 1.0.4
metadata:
  source:
    kind: Community
  support:
    tier: Community
  providers: Microsoft
  categories:
    domains:
    - Security - Others
  author:
    name: Jose Sebastian Canos
triggerOperator: gt
description: |
    'This detection will go over the heartbeats received from the agents of Domain Controllers over the last hour, and will create alerts if the last heartbeats were received an hour ago.'
queryPeriod: 2h
id: b8b8ba09-1e89-45a1-8bd7-691cd23bfa32
entityMappings:
- entityType: Host
  fieldMappings:
  - columnName: Computer
    identifier: HostName
tactics:
- Impact
- DefenseEvasion
name: Missing Domain Controller Heartbeat
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/Heartbeat/MissingDCHearbeat.yaml
query: |
  let query_frequency = 15m;
  let missing_period = 1h;
  //Enter a reference list of hostnames for your DC servers
  let DCServersList = dynamic (["DC01.simulandlabs.com","DC02.simulandlabs.com"]);
  //Alternatively, a Watchlist can be used
  //let DCServersList = _GetWatchlist('HostName-DomainControllers') | project HostName;
  Heartbeat
  | summarize arg_max(TimeGenerated, *) by Computer
  | where Computer in (DCServersList)
  //You may specify the OS type of your Domain Controllers
  //| where OSType == 'Windows'
  | where TimeGenerated between (ago(query_frequency + missing_period) .. ago(missing_period))
  | project TimeGenerated, Computer, OSType, Version, ComputerEnvironment, Type, Solutions
  | sort by TimeGenerated asc  
requiredDataConnectors: []

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/b8b8ba09-1e89-45a1-8bd7-691cd23bfa32')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b8b8ba09-1e89-45a1-8bd7-691cd23bfa32')]",
      "properties": {
        "alertRuleTemplateName": "b8b8ba09-1e89-45a1-8bd7-691cd23bfa32",
        "customDetails": null,
        "description": "'This detection will go over the heartbeats received from the agents of Domain Controllers over the last hour, and will create alerts if the last heartbeats were received an hour ago.'\n",
        "displayName": "Missing Domain Controller Heartbeat",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Computer",
                "identifier": "HostName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/Heartbeat/MissingDCHearbeat.yaml",
        "query": "let query_frequency = 15m;\nlet missing_period = 1h;\n//Enter a reference list of hostnames for your DC servers\nlet DCServersList = dynamic ([\"DC01.simulandlabs.com\",\"DC02.simulandlabs.com\"]);\n//Alternatively, a Watchlist can be used\n//let DCServersList = _GetWatchlist('HostName-DomainControllers') | project HostName;\nHeartbeat\n| summarize arg_max(TimeGenerated, *) by Computer\n| where Computer in (DCServersList)\n//You may specify the OS type of your Domain Controllers\n//| where OSType == 'Windows'\n| where TimeGenerated between (ago(query_frequency + missing_period) .. ago(missing_period))\n| project TimeGenerated, Computer, OSType, Version, ComputerEnvironment, Type, Solutions\n| sort by TimeGenerated asc\n",
        "queryFrequency": "PT15M",
        "queryPeriod": "PT2H",
        "severity": "High",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "Impact"
        ],
        "templateVersion": "1.0.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}