Having hung out with software engineering students for most of my undergrad degree, I wager that there is a computer in a cluster of many, and it is named Mars. (One of the labs at my school named their computers after all the major characters in Hitchhiker's Guide.) The computer named Mars is not functioning and the technicians are replacing a major component - the motherboard is the part that holds most of the other main bits like processor, ram etc.
I don't know what crontabs is short for, but I am guessing it's a bit of programming in the software that controls the whole group of computers, and anything that normally would have been routed to the Mars machine is being sent elsewhere till it's running again.
The fact that everything except the word crontabs made perfect sense to me illustrates the damage that can be done by having three software engineering roommates for two or three years...
Edit - oh well, I figured someone else would have gotten there first.
But maybe I get extra points for knowing it and being female?