Merge pull request #251823 from ericd-mst-github/erd-aib-template-updates

added runAsSystem parameter explanation

Author: prmerger-automator[bot]

articles/virtual-machines/linux/image-builder-json.md

@@ -4,7 +4,7 @@ description: Learn how to create a Bicep file or ARM template JSON template to u
 author: kof-f
 ms.author: kofiforson
 ms.reviewer: erd
-ms.date: 07/17/2023
+ms.date: 09/18/2023
 ms.topic: reference
 ms.service: virtual-machines
 ms.subservice: image-builder
@@ -575,14 +575,16 @@ The `PowerShell` customizer supports running PowerShell scripts and inline comma
     "name":   "<name>",
     "scriptUri": "<path to script>",
     "runElevated": <true false>,
+    "runAsSystem": <true false>,
     "sha256Checksum": "<sha256 checksum>"
   },
   {
     "type": "PowerShell",
     "name": "<name>",
     "inline": "<PowerShell syntax to run>",
     "validExitCodes": [<exit code>],
-    "runElevated": <true or false>
+    "runElevated": <true or false>,
+    "runAsSystem": <true or false>
   }
 ]
 ```
@@ -596,6 +598,7 @@ customize: [
     name:   '<name>'
     scriptUri: '<path to script>'
     runElevated: <true false>
+    runAsSystem: <true false>
     sha256Checksum: '<sha256 checksum>'
   }
   {
@@ -604,6 +607,7 @@ customize: [
     inline: '<PowerShell syntax to run>'
     validExitCodes: [<exit code>]
     runElevated: <true or false>
+    runAsSystem: <true or false>
   }
 ]
 ```
@@ -617,6 +621,7 @@ Customize properties:
 - **inline** – Inline commands to be run, separated by commas.
 - **validExitCodes** – Optional, valid codes that can be returned from the script/inline command. The property avoids reported failure of the script/inline command.
 - **runElevated** – Optional, boolean, support for running commands and scripts with elevated permissions.
+- **runAsSystem** - Optional, boolean, determines whether the PowerShell script should be run as the System user.
 - **sha256Checksum** - generate the SHA256 checksum of the file locally, update the checksum value to lowercase, and Image Builder will validate the checksum during the deployment of the image template.
 
     To generate the sha256Checksum, use the [Get-FileHash](/powershell/module/microsoft.powershell.utility/get-filehash) cmdlet in PowerShell.