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devopsdays MSP 2018: Staying Alive
Ronnie Chen
July 12, 2018
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51 slides
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STAYING ALIVE PATTERNS FOR FAILURE MANAGEMENT FROM THE BOTTOM OF
THE OCEAN 1 — devopsdays MSP 2018 @rondoftw -
TECHNICAL DIVING ▸ longer dive times ▸ deeper dives ▸
overhead ceiling ▸ decompression obligations ▸ more gear. a lot more. ▸ higher pressure ▸ more risks 9 — devopsdays MSP 2018 @rondoftw -
RISKS MAY INCLUDE... 1. hypoxia 2. hyperoxia 3. nitrogen narcosis
4. carbon dioxide buildup 5. oxygen sensor failure 6. deep tissue isobaric counterdiffusion (ICD) 7. high pressure nervous syndrome (HPNS) 8. exhausting your carbon dioxide scrubber 9. carbon dioxide channeling from a poorly packed scrubber 10. carbon buildup causing an spark leading to an oxygen fire. underwater. 11. flooding of breathing loop or circuitry 12. water mixing with the scrubbing agent to produce a toxic caustic soda that will give you chemical burns on your mouth, airway, and lungs 13. plain old decompression sickness 10 — devopsdays MSP 2018 @rondoftw -
If you own a rebreather for five years, two
percent of you are going to die on it. — Jill Heinerth, underwater explorer 11 — devopsdays MSP 2018 @rondoftw -
THIS IS A TALK ABOUT COMMUNICATION AND PROCESS ? ?
? 16 — devopsdays MSP 2018 @rondoftw -
YOU CAME TO HEAR COOL STORIES... 18 — devopsdays MSP
2018 @rondoftw -
BUT YOU'RE GETTING A MEANDERING MEDITATION ON BEST PRACTICES* WHEN
DEALING WITH COMPLEX SYSTEMS INSTEAD * These guidelines have only been shown to work for life or death situations under the ocean. They have not been proven to work for tech. 19 — devopsdays MSP 2018 @rondoftw -
Complex systems are designed to protect against simple failures. 21
— devopsdays MSP 2018 @rondoftw -
CATASTROPHES ARE CAUSED BY A FAILURE CASCADE ▸ you have
a rebreather malfunction ▸ which you would have caught it if you were testing your equipment on a regular basis ▸ your backup tank had a leak and is running low and that wasn't caught either ▸ and your buddy is too far away and isn't checking in with you ▸ and your dive light that you use to communicate at a distance is out of power ▸ and in the excitement you kick up silt and the visibility drops ▸ and in your panic your air consumption goes up and then you breathe through the last of the air in your tank ▸ so you swim for the surface even though you have a decompression obligation 23 — devopsdays MSP 2018 @rondoftw -
A post-mortem that blames this incident on a simple mechanical
malfunction would only cover 12.5% of the issues that led up to this accident. 24 — devopsdays MSP 2018 @rondoftw -
Complex system failures don't happen because a single part of
the system fails. They happen because all the safety procedures that are supposed to stop the failure from cascading didn't work. 25 — devopsdays MSP 2018 @rondoftw -
CORE RULES OF SAFETY SYSTEMS 1. An unused safety system
doesn't exist. 26 — devopsdays MSP 2018 @rondoftw -
NORMALIZATION OF DEVIANCE That natural human tendency, particularly in pressure
circumstances, to take a safety shortcut. — Colonel Mike Mullane, astronaut 27 — devopsdays MSP 2018 @rondoftw -
FALSE FEEDBACK the absence of something bad happening means that
it was safe ADAPTATION experience is no longer a suitable gauge of risk SOCIAL PRESSURE this is just how we do things 28 — devopsdays MSP 2018 @rondoftw -
CORE RULES OF SAFETY SYSTEMS 2. An untested safety system
doesn't exist either! 29 — devopsdays MSP 2018 @rondoftw -
CORE RULES OF SAFETY SYSTEMS 3.Unused or untested safety systems
are more dangerous than not having one at all. Therefore, safety systems must be tested at regular intervals. 30 — devopsdays MSP 2018 @rondoftw -
The length of this interval should be determined not only
by how likely it is for this system to fail but also how great the impact will be if it does. 31 — devopsdays MSP 2018 @rondoftw -
A QUICK SIDENOTE ON ASSESSING RISK ▸ Make assessments based
on likelihood of occurrence. ▸ Make assessments based on magnitude of regret. If you are only evaluating risk based on the chance of it happening, you must be prepared to experience the corresponding level of regret if it does. 32 — devopsdays MSP 2018 @rondoftw -
FAILURE MANAGEMENT ▸ A framework for resiliency ▸ The training
and judgment to use it 35 — devopsdays MSP 2018 @rondoftw -
FAILURE MANAGEMENT FOR SYSTEMS ▸ Have redundancy for systems that
you cannot survive without. ▸ Have a redundant pathway to success: a procedure for graceful degradation for systems that are important but not critical. ▸ Have a process for changing over from primary to redundant systems. 36 — devopsdays MSP 2018 @rondoftw -
FAILURE MANAGEMENT FOR SYSTEMS (CONT) ▸ Keep failures contained so
that they don't bring down other systems ▸ Make it easy to do the right thing and hard to do the dangerous things 37 — devopsdays MSP 2018 @rondoftw -
TRAINING: INEXPERIENCED PEOPLE TO THE FRONT ▸ Most inexperienced person
leads ▸ Experienced person advises, only intervening when necessary ▸ Team is invested in personal success to ensure mission success 40 — devopsdays MSP 2018 @rondoftw -
TRAINING: INEXPERIENCED PEOPLE TO THE FRONT (CONT) ▸ One of
the best ways to equalize a gap in experience ▸ Opportunity to revise and improve problematic systems ▸ Help build good judgment 41 — devopsdays MSP 2018 @rondoftw -
GOOD JUDGMENT Good judgment enables the reshaping of rules and
frameworks to adapt to a changing environment. 42 — devopsdays MSP 2018 @rondoftw -
REFINING JUDGMENT ▸ Post-Mortems ▸ Pre-Mortems ▸ Fire Drills ▸
Revisit Past Decisions 43 — devopsdays MSP 2018 @rondoftw -
POST-MORTEMS ▸ Look at the safety procedures that failed to
stop the cascade ▸ Look for opportunities to create new safety systems at critical points 44 — devopsdays MSP 2018 @rondoftw -
PRE-MORTEMS ▸ Don't wait for failures to build safety frameworks
▸ Identify potential avenues of of failure and make plans for them ▸ Include both likely failures and high regret failures 45 — devopsdays MSP 2018 @rondoftw -
FIRE DRILLS ▸ Vet your plans and safety systems ▸
Perform targeted training ▸ Evaluate effectiveness of tools and documentation 46 — devopsdays MSP 2018 @rondoftw -
REVISIT PAST DECISIONS ▸ Examine successful operations to see what
key insights were helpful ▸ Identify any dependency on luck in previous projects ▸ Share rationale for decisions 47 — devopsdays MSP 2018 @rondoftw -
I WANT TO LEARN MORE! 1. Richard I. Cook -
How Complex Systems Fail 2. Astronaut Mike Mullane - https://www.youtube.com/watch?v=Ljzj9Msli5o 3. Steve Lewis aka decodoppler (Technical Diving Instructor) - Staying Alive 4. Sidney Dekker - Drift into Failure 5. Diane Vaughn - The Challenger Launch Decision 49 — devopsdays MSP 2018 @rondoftw