If You Want to Break Your MacBook, Here’s How

Of course, you can just take a hammer to it or push it off the table, or drop a good 9oz glass Burgundy all over it.

But I should have written the title to “how to screw up your buddy’s MacOS.”

To piss off your buddy, get access to his MacBook and delete /var/db/dslocal/nodes/default/config/

If you can bash, then you have a chance of restoring this. Otherwise, try taking out of the Trash.