I often am asked, why I ask some of the questions I ask during an interview. In some cases some people are not happy and feel that some of the questions are out of line, and some have even said there is no reason to Know these questions in day to day IT work.

One of the first questions I ask is “How does a client\PC find a domain controller”. So why is this important in IT, There are several pieces to this question. But first I know that the majority of IT people can’t answer this question. How do I know this you might ask? well I have interviewed 100’s of people and have found that very few if any could actually answer this questions. often I am looking to see how they respond when they do not know the answer. Most would think that I am looking for the person to say “I do not know” but what I am really looking for is someone to try to walk through how they think it works.

An answer like this would usually sound like, “you know I am not sure of the answer but I based on the information I have right now. I think it works like this” and then attempt to walk through what they think. Interestingly enough the most common answer is “I do not know” If I say something like “that is fine but try to think it through and tell me how you think it might work” I still often get “I do not know”

Now why would knowing the answer be important in a Microsoft IT world. Since all access to all resources is based on authentication and authorization which comes from Active Directory. it is often important to be able to trouble shoot these types of problems. And funny things is one of the most common problems I hear from our customers is “Logging in takes to long” or “Authentication is slow” how can you trouble shoot these types of problems if you do not even understand how a client finds a Domain controller. The first step in authentication is finding what you need to authenticate against.

At the same time how can you design sites and services in active directory. if you do not understand how the client\PC finds a DC in those sites?

This is just one of many questions I ask during an interview and an example as to why it is important to actually understand why and how things work.