The usefulness of knowing the OSI model

I've been reading up on Linux Admin interview questions and also studying for a certification exam. I don't have much practical experience with the OSI model, and the admins that I interact with never really talk about it.

So I'm wondering how much I need to know about the OSI model. Can someone give me an idea as to how they've used knowledge of the OSI model to solve a problem at work? How often do you require knowledge of it to do your job day-to-day? Does it help with trouble-shooting and solving problems? If so, how?

Thank you in advance.