
Ask HN: What is the lifespan of a Raspberry Pi Model A+? - jslakro
I know the SD Card has a defined period of useful life. Besides that, if you run this model continuously, How long will it las?
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gvb
There are reliability estimates based on parts. The one I am slightly familiar
is a military standard MIL-HDBK-217F [https://www.google.com/search?q=+MIL-
HDBK-217F&ie=utf-8&oe=u...](https://www.google.com/search?q=+MIL-
HDBK-217F&ie=utf-8&oe=utf-8)

Doing some searching turns up an online calculator:
[http://aldservice.com/en/Reliability-Software/free-mtbf-
calc...](http://aldservice.com/en/Reliability-Software/free-mtbf-
calculator.html)

FWIW, my expectation is that the above will give you a very precise, but
totally inaccurate, number.

The problem is:

1\. MTBF (and other reliability estimates) are based on a statistical sample
of a large number of items. If your number of items is small(ish), your
statistics become useless.

2\. MTBF is not actually computable until you have a meaningful number of
failures.

3\. Failure rates are very poorly understood, so projecting failure rates
before they occur is difficult.

4\. Projecting the failure rate of a very complex item (recursively - not only
a RPi, but the processor and memory in the RPi) based on estimated failure
rates of each individual part that makes up the item is a combinatorial
nightmare.

To support my assertions above, see Feynman's Appendix to the Rogers
Commission Report on the Space Shuttle Challenger Accident
[http://www.ralentz.com/old/space/feynman-
report.html](http://www.ralentz.com/old/space/feynman-report.html) NASA spent
a large fortune estimating the reliability of the space shuttle and was off by
several orders of magnitude. Granted, the space shuttle was more complex than
a RPi, but expect your estimates, based on the above calculations, to be
equivalently (in)accurate.

