Merge pull request #105878 from iainfoulds/azureadds-classicdeprecation

[AzureADDS] Add formal Classic retirement notice

Author: PRMerger16

articles/active-directory-domain-services/faqs.md

@@ -37,13 +37,15 @@ This page answers frequently asked questions about Azure Active Directory Domain
 No. You can only create a single managed domain serviced by Azure AD Domain Services for a single Azure AD directory.
 
 ### Can I enable Azure AD Domain Services in a Classic virtual network?
-Classic virtual networks aren't supported for new deployments. Existing managed domains deployed in Classic virtual networks continue to be supported. You can also [migrate Azure AD Domain Services from the Classic virtual network model to Resource Manager (preview)](migrate-from-classic-vnet.md).
+Classic virtual networks aren't supported for new deployments. Existing managed domains deployed in Classic virtual networks continue to be supported until they're retired on March 1, 2023. For existing deployments, you can [migrate Azure AD Domain Services from the Classic virtual network model to Resource Manager](migrate-from-classic-vnet.md).
+
+For more information, see the [official deprecation notice](https://azure.microsoft.com/updates/we-are-retiring-azure-ad-domain-services-classic-vnet-support-on-march-1-2023/).
 
 ### Can I enable Azure AD Domain Services in an Azure Resource Manager virtual network?
 Yes. Azure AD Domain Services can be enabled in an Azure Resource Manager virtual network. Classic Azure virtual networks are no longer available when you create a managed domain.
 
 ### Can I migrate my existing managed domain from a Classic virtual network to a Resource Manager virtual network?
-Yes, this feature is in preview. For more information, see [Migrate Azure AD Domain Services from the Classic virtual network model to Resource Manager (preview)](migrate-from-classic-vnet.md).
+Yes. For more information, see [Migrate Azure AD Domain Services from the Classic virtual network model to Resource Manager](migrate-from-classic-vnet.md).
 
 ### Can I enable Azure AD Domain Services in an Azure CSP (Cloud Solution Provider) subscription?
 Yes. For more information, see [how to enable Azure AD Domain Services in Azure CSP subscriptions](csp.md).

articles/active-directory-domain-services/migrate-from-classic-vnet.md

@@ -19,6 +19,11 @@ Azure Active Directory Domain Services (AD DS) supports a one-time move for cust
 
 This article outlines the benefits and considerations for migration, then the required steps to successfully migrate an existing Azure AD DS instance.
 
+> [!NOTE]
+> In 2017, Azure AD Domain Services became available to host in an Azure Resource Manager network. Since then, we have been able to build a more secure service using the Azure Resource Manager's modern capabilities. Because Azure Resource Manager deployments fully replace classic deployments, Azure AD DS classic virtual network deployments will be retired on March 1, 2023.
+>
+> For more information, see the [official deprecation notice](https://azure.microsoft.com/updates/we-are-retiring-azure-ad-domain-services-classic-vnet-support-on-march-1-2023/)
+
 ## Overview of the migration process
 
 The migration process takes an existing Azure AD DS instance that runs in a Classic virtual network and moves it to an existing Resource Manager virtual network. The migration is performed using PowerShell, and has two main stages of execution - *preparation* and *migration*.

articles/active-directory-domain-services/network-considerations.md

@@ -140,6 +140,11 @@ The following network security group rules are required for Azure AD DS to provi
 * For Azure AD DS managed domains that use a Resource Manager-based virtual network, you can restrict inbound access to this port to the *AzureActiveDirectoryDomainServices* service tag.
     * For legacy Azure AD DS managed domains using a Classic-based virtual network, you can restrict inbound access to this port to the following source IP addresses: *52.180.183.8*, *23.101.0.70*, *52.225.184.198*, *52.179.126.223*, *13.74.249.156*, *52.187.117.83*, *52.161.13.95*, *104.40.156.18*, and *104.40.87.209*.
 
+    > [!NOTE]
+    > In 2017, Azure AD Domain Services became available to host in an Azure Resource Manager network. Since then, we have been able to build a more secure service using the Azure Resource Manager's modern capabilities. Because Azure Resource Manager deployments fully replace classic deployments, Azure AD DS classic virtual network deployments will be retired on March 1, 2023.
+    >
+    > For more information, see the [official deprecation notice](https://azure.microsoft.com/updates/we-are-retiring-azure-ad-domain-services-classic-vnet-support-on-march-1-2023/)
+
 ## User-defined routes
 
 User-defined routes aren't created by default, and aren't needed for Azure AD DS to work correctly. If you're required to use route tables, avoid making any changes to the *0.0.0.0* route. Changes to this route disrupt Azure AD Domain Services and puts the managed domain in an unsupported state.