The hardest part of transitioning from traditional management to modern management for Windows 10 is deciding whether to use on-premises AD, Azure AD, or a hybrid of the two. In this article, we’ll compare AD DS to Azure AD and see what our standard Active Directory can do that Azure AD can’t. We will also see how Microsoft installs hybrid solutions and why this method can be beneficial for certain companies.
Once upon a time, every Windows business was flat. Active Directory was the only container that stored all of your domain data objects. We just called it AD back then because it was the only AD form. It was supported by the three pillars: domain controllers, DNS and group policy. It was an architecture that served many companies well for nearly two decades. And then came Azure, and suddenly traditional AD is now called legacy AD in some circles. Azure AD, of course, exists in the cloud, that wonderful destination that it seems most organizations want to migrate to. Because it is cloud-native, it uses different protocols and methodologies for account authentication and policy enforcement. In some ways, on-premises AD and Azure AD are like water and oil because they are so different.
Learn more: What is Azure? Fundamentals, services and pricing in 2022
Key Differences Between On-Premises AD, Hybrid Azure AD Join, and Azure AD
The main limitation of local AD
Many companies began their migration to the cloud years ago. Yet the remote work revolution of 2020 was like pouring kerosene on an existing flame. That’s when the remote work revolution began. The limitation of Legacy AD significantly inhibits its ability to support hybrid worker architectures. It requires domain-joined computers to have a site line to a domain controller. This makes it impossible for employees to connect to the corporate network when working from a remote workspace such as their home office or hotel room. The only way to achieve AD connectivity then is through a VPN connection. This makes the process of onboarding a new computer difficult at best. Additionally, your VPN infrastructure can quickly become a bottleneck when many users are using it. VPN then requires remote access and routing policies to enforce least privilege security so that remote users do not have access to the entire network.
The modern world of full transition to Azure AD
If you’re a Windows administrator, you’re probably familiar with the concept of deactivation, which recovers accidental deletions of objects in AD. Azure AD is a way to permanently disable your on-premises AD servers. No more worrying about AD sync or DNS scavenging. Everything now exists in the cloud, where Azure-joined users and computers will authenticate. Azure-joined computers only need an internet connection to authenticate, negating the need for AD connectivity. Suddenly users can work from anywhere without the hassle of a problematic VPN. Microsoft 365 uses Azure Active Directory (Azure AD) to manage user identities, so employees are automatically signed in on their corporate devices.
The real beauty of Azure AD becomes apparent when provisioning devices. Windows computers joined to the cloud domain and configured on autopilot can be shipped directly from the original equipment manufacturer (OEM) to the standby user, regardless of location. The user opens the box, powers up the device, and logs in using their Azure AD credentials. After the Autopilot completes the process of setting up the device, Microsoft Endpoint Management, also known as Intune, steps in to deliver all configuration settings, policies, and applications assigned to that machine. Within hours, the user is ready to start working. Suppose the machine has a chipset that allows remote access to its BIOS and technicians to perform remote reboots even when the operating system is not operational. In this case, you suddenly have an IT estate that can be deployed, implemented and supported without local support. Welcome to the hybrid world.
Not everyone can move directly to Azure AD
Migrating your on-premises AD infrastructure to cloud native is a giant leap, but not everyone can do it overnight. Some of the reasons include the following:
- You still support Windows devices with legacy operating systems, such as Windows 7.
- You rely on an existing imaging solution to deploy and configure devices that you are not yet ready to abandon.
- Some of your user devices have Win32 applications that rely on legacy AD machine authentication.
And finally, there’s Group Policy and Group Policy Preferences. Many companies have a large portfolio of Group Policy Objects (GPOs) that they have created to provide managed configuration and security settings for users and computers over the years. The equivalent of Group Policy is an MDM provider such as the previously mentioned Microsoft Endpoint Manager. Although MDMs can provide settings configurations to computers regardless of their location, the list of available settings is not as extensive as the combined range of GP and GPP. Although Microsoft has made great strides in closing the parity gap between the two, the disparity between the two remains. For large enterprises that rely heavily on Group Policy, insufficient coverage of MDM settings may be enough to hold them back for the time being.
Learn more: How Revertible Passwords Compromise Active Directory Security
Hybrid Azure AD join as a transitional compromise
If you can’t jump directly to Azure AD right now, a third option called Hybrid Azure AD join. Hybrid Azure AD join maintains the legacy trust relationship that your client devices have with on-premises AD while simultaneously creating a trust relationship stored in Azure AD. This dual enrollment gives your device visibility in the cloud so users can use single sign-on when accessing their Microsoft 365 apps. It also provides self-service password reset and password reset capabilities. Windows Hello PIN code for your users, regardless of their location. You can create device-based Conditional Access policies requiring devices to meet compliance requirements before being allowed access to corporate resources to improve your security.
Like traditional AD, Hybrid Azure AD Join relies on Group Policy to centrally manage settings configurations, so the GPO wallet you’ve spent so much time on will be still used. Unfortunately, Group Policy still relies on AD connectivity, and computers must be line-of-sight to authenticate AD users who don’t have cached credentials. You will also need to install Azure AD Connect on an on-premises server to sync data between on-premises AD and Azure AD so that users have the same credentials in both worlds. This means one more thing your IT team will need to manage and support. Like any hybrid architecture, it adds complexity to your network, which adds complexity to its support.
Let’s say you have visited the Microsoft certification portal within the past two years. In this case, you will notice that they no longer offer certification paths in their traditional operating systems and on-premises architectures. Everything revolves around the cloud. Although you may not be ready to take the leap just yet, the day will come when you will be forced to begin the transition to Azure AD to access the latest technologies and solution innovations. For some, hybrid Azure AD join may be an edible path to get there.