[DarronWyke]

Sysadmin/infosec guy here. We do the same thing. I was shown this a while ago and I use it on other candidates I've interviewed. Propose a problem, then as they start working through it, throw other wrenches into it or state that their solution didn't work. See what tangents they go off to.

Another neat one I was shown was, as a whiteboard test, was to write down all the letters, A-Z, then come up with the name of a command for each letter. It's a double-sided test -- it shows your ability to respond quickly, how you respond, and the ability to back up your responses.

Of course, joking questions like "vi or emacs?" can be good as well to see a candidate's character as to how they respond to technical inside jokes like that.

[viraptor]

Not sure about the alphabet. Got to K before I got stuck and thought... So in that moment, if I forget that there's kill that starts with a K, why does it matter? How does it relate to the fact that I know to use kill for sending signals? The recall for a situation where you'd use something and for a letter matching game seem to be very separate. (On the other hand I remembered join which I used maybe once in my life...)

[DarronWyke]

It's multi-faceted. It shows your ability to think quick and how you solve multiple problems. If you stop in the middle of the list and try over and over to come up with an answer, how will you react to a real problem? Or do you just give up when it gets hard?

It's testing more than just rote memorization. You also have to explain any commands you write down, what they do.