A Big Red Switch often includes a molly-guard, a cover that must be lifted to trip the switch. The original molly-guard was jury-rigged from plexiglass to prevent a programmer's young daughter Molly from pressing the BRS on an IBM 4341 server, after she had done so twice in one day.
Similarly, molly-guard is a package on Debian-based Linux distributions that traps shutdown and reboot commands over SSH, and confirms the machine is the correct machine by requiring the user to type the hostname of the system before the event will proceed. This helps prevent the user from inadvertently shutting down the wrong system.
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