donuts = D = DoS attack

doorstop n.

Used to describe equipment that is non-functional and halfway expected to remain so, especially obsolete equipment kept around for political reasons or ostensibly as a backup. "When we get another Wyse-50 in here, that ADM 3 will turn into a doorstop." Compare boat anchor.

--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.