NGINX - Multiple server errors from single IP address

let threshold = 100;
NGINXHTTPServer
| where tolong(HttpStatusCode) >= 500 and tolong(HttpStatusCode) <= 599 
| summarize MultipleServerErrors = count() by SrcIpAddr, bin(TimeGenerated, 5m)
| where MultipleServerErrors > threshold
| extend IPCustomEntity = SrcIpAddr

triggerOperator: gt
queryFrequency: 1h
description: |
    'Detects multiple server errors from one source in short timeframe'
status: Available
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: NGINXHTTPServer
  dataTypes:
  - NGINXHTTPServer
version: 1.0.0
queryPeriod: 1h
name: NGINX - Multiple server errors from single IP address
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/NGINX HTTP Server/Analytic Rules/NGINXMultipleServerErrorsFromSingleIP.yaml
id: b3ae0033-552e-4c3c-b493-3edffb4473bb
tactics:
- Impact
- InitialAccess
relevantTechniques:
- T1498
- T1190
- T1133
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
  entityType: IP
query: |
  let threshold = 100;
  NGINXHTTPServer
  | where tolong(HttpStatusCode) >= 500 and tolong(HttpStatusCode) <= 599 
  | summarize MultipleServerErrors = count() by SrcIpAddr, bin(TimeGenerated, 5m)
  | where MultipleServerErrors > threshold
  | extend IPCustomEntity = SrcIpAddr  

{
  "$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/b3ae0033-552e-4c3c-b493-3edffb4473bb')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b3ae0033-552e-4c3c-b493-3edffb4473bb')]",
      "properties": {
        "alertRuleTemplateName": "b3ae0033-552e-4c3c-b493-3edffb4473bb",
        "customDetails": null,
        "description": "'Detects multiple server errors from one source in short timeframe'\n",
        "displayName": "NGINX - Multiple server errors from single IP address",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPCustomEntity",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/NGINX HTTP Server/Analytic Rules/NGINXMultipleServerErrorsFromSingleIP.yaml",
        "query": "let threshold = 100;\nNGINXHTTPServer\n| where tolong(HttpStatusCode) >= 500 and tolong(HttpStatusCode) <= 599 \n| summarize MultipleServerErrors = count() by SrcIpAddr, bin(TimeGenerated, 5m)\n| where MultipleServerErrors > threshold\n| extend IPCustomEntity = SrcIpAddr\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact",
          "InitialAccess"
        ],
        "techniques": [
          "T1133",
          "T1190",
          "T1498"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}