Manage security after upgrading Azure Local

Artikkeli
12/11/2024

Applies to: Azure Local, version 23H2

This article describes how to manage security settings on an Azure Local that was upgraded from version 22H2 to version 23H2.

Prerequisites

Before you begin, make sure that you have access to an Azure Local, version 23H2 system that was upgraded from version 22H2.

Post upgrade security changes

When you upgrade your Azure Local from version 22H2 to version 23H2, the security posture of your system doesn't change. We strongly recommend that you update the security settings after the upgrade to benefit from enhanced security.

Here are the benefits of updating the security settings:

Improves the security posture by disabling legacy protocols and ciphers, and hardening your deployment.
Reduces Operating Expense (OpEx) with a built-in drift protection mechanism for consistent at-scale monitoring via the Azure Arc Hybrid Edge baseline.
Enables you to closely meet Center for Internet Security (CIS) benchmarks and Defense Information System Agency (DISA) Security Technical Implementation Guide (STIG) requirements for the OS.

Make these high-level changes after the upgrade is complete:

Apply the security baseline.
Apply encryption at-rest.
Enable Application Control.

Each of these steps is described in detail in the following sections.

Apply security baselines

A new deployment of Azure Local introduces two baselines documents injected by the security management layer, while the upgraded cluster doesn't.

Important

After applying the security baseline documents, a new mechanism is used to apply and maintain the Security baseline settings.

If your servers inherit baseline settings through mechanisms such as GPO, DSC, or scripts, we recommend that you:
- Remove these duplicate settings from such mechanisms.
- Alternatively, after applying the security baseline, Disable the drift control mechanism.
The new security posture of your servers will combine the previous settings, the new settings, and the overlapping settings with updated values.

Note

Microsoft tests and vaildates the Azure Local, version 23H2 security settings. We strongly recommend that you keep these settings. Use of custom settings can potentially lead to system instability, incompatibility with the new product scenarios, and could require extensive testing and troubleshooting on your part.
When running the followign commands, you'll find the documents aren't in place. These cmdlets won't return any output.
```
Get-AzSSecuritySettingsConfiguration
Get-AzSSecuredCoreConfiguration
```
To enable the baselines, go to each of the nodes you upgraded. Run the following commands locally or remotely using a privileged administrator account:
```
Start-AzSSecuritySettingsConfiguration
Start-AzSSecuredCoreConfiguration
```
Reboot the nodes in a proper sequence for the new settings to become effective.

Confirm the status of the security baselines

After rebooting, rerun the cmdlets to confirm the status of the security baselines:

Get-AzSSecuritySettingsConfiguration
Get-AzSSecuredCoreConfiguration

You'll get an output for each cmdlet with the baseline information.

Here is an example of the baseline output:

OsConfiguration": {
"Document": {
"schemaversion": "1.0",
"id": "<GUID>", "version": "1.0",
"context": "device",
"scenario": "ApplianceSecurityBaselineConfig"

Enable encryption at-rest

During the upgrade, Microsoft detects if your system nodes have BitLocker enabled. If BitLocker is enabled, you're prompted to suspend it. If you previously enabled BitLocker across your volumes, resume the protection. No further steps are required.

To verify the status of encryption across your volumes, run the following commands:

Get-AsBitlocker -VolumeType BootVolume
Get-AsBitlocker -VolumeType ClusterSharedVolume

If you need to enable BitLocker on any of your volumes, see Manage BitLocker encryption on Azure Local.

Enable Application Control

Application control for business (formerly known as Windows Defender Application Control or WDAC) provides a great layer of defense against running untrusted code.

After you've upgraded to version 23H2, consider enabling Application Control. This can be disruptive if the necessary measures aren't taken for proper validation of existing third party software already existing on the servers.

For new deployments, Application Control is enabled in Enforced mode (blocking nontrusted binaries), whereas for upgraded systems we recommend that you follow these steps:

Enable Application Control in Audit mode (assuming unknown software might be present).
Monitor Application Control events.
Create the necessary supplemental policies.
Repeat steps #2 and #3 as necessary until no further audit events are observed. Switch to Enforced mode.

Warning

Failure to create the necessary AppControl policies to enable additional third party software will prevent that software from running.

For instructions to enable in Enforced mode, see Manage Windows Defender Application Control for Azure Local.

Next steps

Understand BitLocker encryption.

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