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Comment by jomkr | Hacker News Reader

I'm not sure that 55 months of up-time indicates it's more or less likely to go down in the next month, but I'd guess more likely.

Surely there are options, have you tried de-compiling the source from the binary?

>but the physical config was accidentally overwritten and there are no backups

Any old dev PCs lying around somewhere? It's worth reaching out to the old developers to see if they have a copy, in really old legacy systems it's fairly likely someone will have a copy somewhere.

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> reaching out to the old developers to see if they have a copy

I think you mean "older devs that are still with the company" but I was once contacted by a former employer for exactly this: they had lost source code for the billing system. I didn't have the source code so that was easy to answer. Developers that have stolen intellectual property from former employers may want to consider carefully how they answer such questions...

Also, I was never supposed to have had access to this code whilst I was employed so I did wonder if there was more to it than just "oops we lost it can you help?". Perhaps they were trying to chase down a leak or something? I never heard back though (they survived).

If you barge in, lawyers blazing, shouting about "stolen intellectual property", the likely response is "don't have any, never had", regardless of its veracity. OTOH, "disks that are left unerased by accident" _and_ generally being very open on the nature of the emergency is much more likely to bring help.

This case is one I'd be pretty careful about though as a former employee - the situation the company's found themselves in is pretty indicative of mismanagement, and desperate people do desperate things.

IANAL, but a hold harmless agreement would be a simple CYA that I'd do if I was personally in this situation.

Indeed. That's why I wrote, in essence "if you start with 'you surely HAVE our code, GIMME!!!!!'", the answer will always be 'nope', regardless of facts".

> I'm not sure that 55 months of up-time indicates it's more or less likely to go down in the next month, but I'd guess more likely.

Less likely

https://en.wikipedia.org/wiki/Lindy_Effect

> The Lindy effect is a theory that the future life expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy. Where the Lindy effect applies, mortality rate decreases with time. In contrast, living creatures and mechanical things follow a bathtub curve where, after "childhood", the mortality rate increases with time. Because life expectancy is probabilistically derived, a thing may become extinct before its "expected" survival. In other words, one needs to gauge both the age and "health" of the thing to determine continued survival.

It's going to be some mix of Lindy and bathtub. Lindy for the software itself and electronics, bathtub for fans, spinning disks, cables, other things that may physically degrade.

Also, unless the server is in a data centre with some serious redundancies, (and even then...) the power is guaranteed to go down one day.

Ideas and technologies are actively sustained by external forces due to perceived merit in said ideas or technologies.

A computer program that is freewheeling along, by contrast, is not sustained by but dependent on external factors (software, hardware, electricity), all of which are prone to fail and some of which are more likely to fail with age.

OP is talking about a phyaical server. The Lindy Effect is for "some non-perishable things". A server that already has already been running for at least 55 monthes is definitely perishable.

A server running software has both perishable and non-perishable elements. The physical hardware is perishable and weakens with age, but as the software itself ages the likelihood that it contains bugs like "it crashes whenever daylight savings occurs" decreases.

The question is which effect dominates at a particular point in time.

Its hardware, so you are looking at the bathtub curve https://en.wikipedia.org/wiki/Bathtub_curve

Well, at least that's a plus for non-compiled languages (PHP, JS etc.): even if everything else fails, you still have the code on the server.

But I guess the bigger problem here is the missing config - as long as you still have the binary of the application, you should be able to restart it.

> I'm not sure that 55 months of up-time indicates it's more or less likely to go down in the next month, but I'd guess more likely.

If 'going down' is an event governed by chance (e.g. power failure), then it does not matter if it has been up for 55 months or 55 minutes.

https://en.wikipedia.org/wiki/Gambler%27s_fallacy

There’s also the Turkey fallacy - Turkeys that are smug about knowing the Gambler’s fallacy keep thinking their survival is independent of their age, until people eat them. My probability of dying goes up with each year as well, it’s not constant.

Think the probability of the machine shutting down in the next minute is independent of age, but it shutting off in the next 100 years is certain. There’s a line or curve that should indicate probability of shutting down before OP writes the replacement.

This is how I feel when people talk about Schroedingers cat. Give me a week and I'll be able to answer that question definitively.

It depends on what kind of chance we are talking about.

See eg https://en.wikipedia.org/wiki/Bathtub_curve for a common way to fail. Or https://en.wikipedia.org/wiki/Reliability_engineering in general.

You are right about some specific kinds of spontaneous failures. (Though not sure if external power failures are distributed that way.)

Gambler's Fallacy is applicable "when it has otherwise been established that the probability of such events does not depend on what has happened in the past" -- not the case here.

The fact that the server has been running uninterrupted for 55 months is a strong clue that the power to this system is robust, not subject to "random" power loss scenarios like one would expect at a typical residence.

> The fact that the server has been running uninterrupted for 55 months is a strong clue that the power to this system is robust, not subject to "random" power loss scenarios like one would expect at a typical residence.

I don't remember random power losses in typical first world residences after perhaps the 1990s?

I get them at my house. Every time there's an ice storm. And for a while there was an intermittent issue where floodwaters came up over my internet port in the junction box, and so my internet would go out for a while. Hopefully the power grid isn't as janky.

Interesting! I guess I never lived either in rural areas or anywhere with ice storms.

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