What is OSD

OSD is more than just a ConfigMgr feature; it is a methodology, even a mind-set for deploying Windows. At its core, OSD is about delivering a new instance of Windows to Windows-compatible devices, en masse. Although that sounds simple, it isn't always as easy as it sounds because of the philosophy and architecture of Windows-namely to support commodity hardware without restriction.

Mass delivery of Windows is nothing new. Organizations have been using third-party tools since the last century to capture an "image" of a single system and copy it to other systems. Windows is tolerant of this and starting with Windows Vista, Windows is even installed by the Windows setup routine using an "image."

What sets OSD apart? What makes it stand far above the crowd?

• OSD is about automating the entire process, from image creation and image maintenance to actual image deployment.
• OSD is not just about creating and deploying an image. OSD is an entire process that allows you to define actions before the image is applied to a system (such as partitioning and formatting the drive or even BIOS upgrades) and actions after the image is applied (such as software update installation or application deployment).
• OSD is dynamic, enabling different yet automatic deployment time behavior based on an unbounded set of criteria including things such as hardware type, location, and intended user or system roles.
• OSD is extensible to meet the needs of any organization. MDT and its subset feature User Driven Installation (UDI) are excellent examples of this extensibility from Microsoft, and OSD App Tree and OSD++ are excellent examples from a source other than Microsoft that are also widely used.
• OSD is integrated into ConfigMgr, which allows you to take advantage of the other powerful features of the product including software distribution, software updates, and reporting, all from a single management console in a seamless manner.

MDT is a free and fully supported solution from Microsoft that is both a complete standalone solution for deploying Windows and an add-on to base functionality of OSD in ConfigMgr. As an add-on for OSD, MDT brings a great deal of commonly needed functionality and makes the deployment process dynamic and database-driven.
Listing the complete capabilities MDT adds to OSD would be a large list; suffice it to say the functionality in MDT is often summarized as addressing issues and problems you never knew you had. Although the OSD toolset is clearly focused on providing flexibility, power, and tools that integrates with ConfigMgr enabling you to deploy Windows, MDT is focused on providing a complete, end-to-end solution for nearly every Windows deployment challenge and scenario. This essentially means MDT is a details-focused solution aimed at solving common challenges faced by most organizations when deploying Windows.
MDT does add complexity to OSD in the form of additional moving parts such as configuration files, a separate workbench, and an optional database. These increase your learning curve and sometimes overwhelm those just beginning to learn OSD. MDT also hides some of the lower-level details of OSD, making it more difficult to troubleshoot. In addition, the database component is not necessarily enterprise-friendly in its default form because it is a single instance sitting at a single physical location.
Just installing MDT does not force you to use it. Thus, it is highly recommended you at least review the capabilities of MDT and even install it to examine it fully.