[conspire] Package: molly-guard

Rick Moen rick at linuxmafia.com
Sun Apr 4 20:14:58 PDT 2021

A classic from The Jargon File has apparently been instantiated in
software (to prevent you, in essence, from shutting down or rebooting
the wrong machine by accident).  

  Package: molly-guard (0.7.2)
  protects machines from accidental shutdowns/reboots

  The package installs a shell script that overrides the existing
  commands and first runs a set of scripts, which all have to exit
  successfully, before molly-guard invokes the real command.

  One of the scripts checks for existing SSH sessions. If any of the four
  commands are called interactively over an SSH session, the shell script
  prompts you to enter the name of the host you wish to shut down. This
  should adequately prevent you from accidental shutdowns and reboots.

  molly-guard diverts the real binaries to /lib/molly-guard/. You can
  bypass molly-guard by running those binaries directly.


I love it.  For those who aren't familiar with the legend of Molly:

  molly-guard (n)

  [University of Illinois] A shield to prevent tripping of some Big Red
  Switch by clumsy or ignorant hands.  Originally used of the plexiglass
  covers improvised for the BRS on an IBM 4341, after a programmer's
  toddler daughter (named Molly) frobbed it twice in one day.  Later
  generalized to covers over stop/reset switches on disk drives and
  networking equipment.  In hardware catalogues, you'll see the much
  less interesting description “guarded button”.


The IBM 4300 series were 1980s mid-range mainframes with modest
electrical requirements so they could live outside data centres, 
in regular business premises, were compatible with System/370, and
ran any of several Armonk mainframe OSes of the day.  I think all of
those OSes except VM/370 were dead ends.  VM/370's modern offspring is 
the z/VM virtual machine software architecture for IBM's 64-bit
z/Architecture hardware.  (I've been away from mainframes so long
that I know little more about this.)

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