

If you start with a default configuration of directory synchronization and then configure filtering, the objects that are filtered out are no longer synchronized to Azure AD.

In Azure AD Connect sync, you can enable filtering at any time. As a result, Microsoft can't provide technical support for such deployments. Any of these actions might result in an inconsistent or unsupported state of Azure AD Connect sync. Microsoft doesn't support modifying or operating Azure AD Connect sync outside of the actions that are formally documented. This article covers how to configure the different filtering methods. But in Azure AD, you only want active accounts to be present.

In the small pilot, it's not important to have a complete Global Address List to demonstrate the functionality. You run a pilot for Azure or Microsoft 365 and you only want a subset of users in Azure AD.In some cases however, you're required to make some changes to the default configuration. With the default configuration, they would have the same experience that they would have with an on-premises implementation of Exchange or Lync. Users using Microsoft 365 workloads, such as Exchange Online and Skype for Business, benefit from a complete Global Address List so they can send email and call everyone. In general, this is the recommended configuration. The default configuration takes all objects in all domains in the configured forests. By using filtering, you can control which objects appear in Azure Active Directory (Azure AD) from your on-premises directory.
