Merge pull request #187408 from MicrosoftGuyJFlo/StaleDevicesUpdate

[Azure AD] Devices - Stale devices update

Author: LJSpiller

articles/active-directory/devices/manage-stale-devices.md

@@ -6,7 +6,7 @@ services: active-directory
 ms.service: active-directory
 ms.subservice: devices
 ms.topic: how-to
-ms.date: 06/02/2021
+ms.date: 02/07/2022
 
 ms.author: joflore
 author: MicrosoftGuyJFlo
@@ -19,13 +19,13 @@ ms.collection: M365-identity-device-management
 ---
 # How To: Manage stale devices in Azure AD
 
-Ideally, to complete the lifecycle, registered devices should be unregistered when they are not needed anymore. However, due to, for example, lost, stolen, broken devices, or OS reinstallations you typically have stale devices in your environment. As an IT admin, you probably want a method to remove stale devices, so that you can focus your resources on managing devices that actually require management.
+Ideally, to complete the lifecycle, registered devices should be unregistered when they aren't needed anymore. Because of lost, stolen, broken devices, or OS reinstallations you'll typically have some stale devices in your environment. As an IT admin, you probably want a method to remove stale devices, so that you can focus your resources on managing devices that actually require management.
 
 In this article, you learn how to efficiently manage stale devices in your environment.
 
 ## What is a stale device?
 
-A stale device is a device that has been registered with Azure AD but has not been used to access any cloud apps for a specific timeframe. Stale devices have an impact on your ability to manage and support your devices and users in the tenant because: 
+A stale device is a device that has been registered with Azure AD but hasn't been used to access any cloud apps for a specific timeframe. Stale devices have an impact on your ability to manage and support your devices and users in the tenant because: 
 
 - Duplicate devices can make it difficult for your helpdesk staff to identify which device is currently active.
 - An increased number of devices creates unnecessary device writebacks increasing the time for Azure AD connect syncs.
@@ -35,7 +35,7 @@ Stale devices in Azure AD can interfere with the general lifecycle policies for
 
 ## Detect stale devices
 
-Because a stale device is defined as registered device that hasn't been used to access any cloud apps for a specific timeframe, detecting stale devices requires a timestamp-related property. In Azure AD, this property is called **ApproximateLastLogonTimestamp** or **activity timestamp**. If the delta between now and the value of the **activity timestamp** exceeds the timeframe you have defined for active devices, a device is considered to be stale. This **activity timestamp** is now in public preview.
+Because a stale device is defined as a registered device that hasn't been used to access any cloud apps for a specific timeframe, detecting stale devices requires a timestamp-related property. In Azure AD, this property is called **ApproximateLastLogonTimestamp** or **activity timestamp**. If the delta between now and the value of the **activity timestamp** exceeds the timeframe you've defined for active devices, a device is considered to be stale. This **activity timestamp** is now in public preview.
 
 ## How is the value of the activity timestamp managed?  
 
@@ -79,7 +79,7 @@ Define a timeframe that is your indicator for a stale device. When defining your
 
 ### Disable devices
 
-It is not advisable to immediately delete a device that appears to be stale because you can't undo a deletion if there is a false positive. As a best practice, disable a device for a grace period before deleting it. In your policy, define a timeframe to disable a device before deleting it.
+It isn't advisable to immediately delete a device that appears to be stale because you can't undo a deletion if there's a false positive. As a best practice, disable a device for a grace period before deleting it. In your policy, define a timeframe to disable a device before deleting it.
 
 ### MDM-controlled devices
 
@@ -99,30 +99,30 @@ To clean up Azure AD:
 - **Windows 7/8** - Disable or delete Windows 7/8 devices in your on-premises AD first. You can't use Azure AD Connect to disable or delete Windows 7/8 devices in Azure AD. Instead, when you make the change in your on-premises, you must disable/delete in Azure AD.
 
 > [!NOTE]
->* Deleting devices in your on-premises AD or Azure AD does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g. Conditional Access). Read additional information on how to [remove registration on the client](faq.yml).
->* Deleting a Windows 10 device only in Azure AD will re-synchronize the device from your on-premises using Azure AD connect but as a new object in "Pending" state. A re-registration is required on the device.
->* Removing the device from sync scope for Windows 10/Server 2016 devices will delete the Azure AD device. Adding it back to sync scope will place a new object in "Pending" state. A re-registration of the device is required.
->* If you are not using Azure AD Connect for Windows 10 devices to synchronize (e.g. ONLY using AD FS for registration), you must manage lifecycle similar to Windows 7/8 devices.
+> - Deleting devices in your on-premises AD or Azure AD does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g. Conditional Access). Read additional information on how to [remove registration on the client](faq.yml).
+> - Deleting a Windows 10 device only in Azure AD will re-synchronize the device from your on-premises using Azure AD connect but as a new object in "Pending" state. A re-registration is required on the device.
+> - Removing the device from sync scope for Windows 10/Server 2016 devices will delete the Azure AD device. Adding it back to sync scope will place a new object in "Pending" state. A re-registration of the device is required.
+> - If you are not using Azure AD Connect for Windows 10 devices to synchronize (e.g. ONLY using AD FS for registration), you must manage lifecycle similar to Windows 7/8 devices.
 
 ### Azure AD joined devices
 
 Disable or delete Azure AD joined devices in the Azure AD.
 
 > [!NOTE]
->* Deleting an Azure AD device does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g Conditional Access). 
->* Read more on [how to unjoin on Azure AD](faq.yml) 
+> - Deleting an Azure AD device does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g Conditional Access). 
+> - Read more on [how to unjoin on Azure AD](faq.yml) 
 
 ### Azure AD registered devices
 
 Disable or delete Azure AD registered devices in the Azure AD.
 
 > [!NOTE]
->* Deleting an Azure AD registered device in Azure AD does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g. Conditional Access).
->* Read more on [how to remove a registration on the client](faq.yml)
+> - Deleting an Azure AD registered device in Azure AD does not remove registration on the client. It will only prevent access to resources using device as an identity (e.g. Conditional Access).
+> - Read more on [how to remove a registration on the client](faq.yml)
 
 ## Clean up stale devices in the Azure portal  
 
-While you can clean up stale devices in the Azure portal, it is more efficient, to handle this process using a PowerShell script. Use the latest PowerShell V2 module to use the timestamp filter and to filter out system-managed devices such as Autopilot.
+While you can clean up stale devices in the Azure portal, it's more efficient, to handle this process using a PowerShell script. Use the latest PowerShell V2 module to use the timestamp filter and to filter out system-managed devices such as Autopilot.
 
 A typical routine consists of the following steps:
 
@@ -156,11 +156,26 @@ $dt = (Get-Date).AddDays(-90)
 Get-AzureADDevice -All:$true | Where {$_.ApproximateLastLogonTimeStamp -le $dt} | Set-AzureADDevice -AccountEnabled $false
 ```
 
+### Delete devices
+
+> [!CAUTION]
+> The `Remove-AzureADDevice` cmdlet does not provide a warning. Running this command will delete devices without prompting. **There is no way to recover deleted devices**.
+
+Before deleting any devices, back up any BitLocker recovery keys you may need in the future. There's no way to recover BitLocker recovery keys after deleting the associated device.
+
+Building on the [disable devices example](#disable-devices) we look for disabled devices, now inactive for 120 days, and pipe the output to `Remove-AzureADDevice` to delete those devices.
+
+```powershell
+$dt = (Get-Date).AddDays(-120)
+$state = $false
+Get-AzureADDevice -All:$true | Where {($_.ApproximateLastLogonTimeStamp -le $dt) -and ($_.AccountEnabled -le $state)} | Remove-AzureADDevice
+```
+
 ## What you should know
 
 ### Why is the timestamp not updated more frequently?
 
-The timestamp is updated to support device lifecycle scenarios. This attribute is not an audit. Use the sign-in audit logs for more frequent updates on the device.
+The timestamp is updated to support device lifecycle scenarios. This attribute isn't an audit. Use the sign-in audit logs for more frequent updates on the device.
 
 ### Why should I worry about my BitLocker keys?
 
@@ -169,9 +184,10 @@ When configured, BitLocker keys for Windows 10 devices are stored on the device
 ### Why should I worry about Windows Autopilot devices?
 
 When you delete an Azure AD device that was associated with a Windows Autopilot object the following three scenarios can occur if the device will be repurposed in future:
+
 - With Windows Autopilot user-driven deployments without using pre-provisioning, a new Azure AD device will be created, but it won’t be tagged with the ZTDID.
-- With Windows Autopilot self-deploying mode deployments, they will fail because an associate Azure AD device cannot be found.  (This failure is a security mechanism to make sure that no “imposter” devices try to join Azure AD with no credentials.) The failure will indicate a ZTDID mismatch.
-- With Windows Autopilot pre-provisioning deployments, they will fail because an associated Azure AD device cannot be found. (Behind the scenes, pre-provisioning deployments use the same self-deploying mode process, so they enforce the same security mechanisms.)
+- With Windows Autopilot self-deploying mode deployments, they'll fail because an associate Azure AD device can’t be found.  (This failure is a security mechanism to make sure that no “imposter” devices try to join Azure AD with no credentials.) The failure will indicate a ZTDID mismatch.
+- With Windows Autopilot pre-provisioning deployments, they'll fail because an associated Azure AD device can’t be found. (Behind the scenes, pre-provisioning deployments use the same self-deploying mode process, so they enforce the same security mechanisms.)
 
 ### How do I know all the type of devices joined?