This chapter provided you with an overview of AD DR and how a DR guide fits into your organization's Business Continuity plan. It also provided you with a brief overview of the scenarios that will be addressed by this book. As you will have noticed by now, the subject of DR with an AD is much deeper and more crucial than you might think.

Microsoft's focus on pointing out the de-centralized architecture of AD is true, and it really does work for small incidents, for connection error, and so on. The picture is very different, however, when we look at how complex and devastating AD failure can be in some situations, and how crucial it is to have a proper recovery guide in place.

It is important to understand that the risks and threats discussed here exist in very real forms. In today's multi-platform environments and heterogeneous networks, there may be services and systems that authenticate against AD which probably didn't figure in your initial designs, but had to be added to the actual schema.

All these things make your infrastructure all the more mission-critical. If you want to use an analogy would you rather have insurance for your house that covers all your valuable items but not the house or one that covers the house as well?