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PawelDecowski

Reminded me of “The case of the 500-mile email”: http://www.ibiblio.org/harris/500milemail.html

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Or the "Car allergic to vanilla ice cream" tale.

http://www.cgl.uwaterloo.ca/~smann/IceCream/humor.html

Or the "OpenOffice can't print on Tuesdays" bug https://bugs.launchpad.net/ubuntu/+source/cupsys/+bug/255161...

That one reminds me of the system I worked on years ago that wouldn't accept credit cards that expired in August or September (of any year).

I bet it was a Javascript system that tried to interpret month numbers of 08 and 09 as octal because of the leading zero. Am I close?

That's clearly a tale rather than a true event. The guy would have noticed during other extremely short trips that his car wouldn't start afterwards.

I was impressed that the users were able to troubleshoot the fault that specifically in the first place.

Also, that it's pretty clear that they were only able to do so because they had limited technical knowledge of email: to someone who runs a mail server, the idea of email not getting further than 500 miles is ridiculous and absurd. To someone not used to it, not so much...

I'm sure there's a cute name for this specific variety of irony, but I don't know what it is.

I think it had a little bit to do with the users being statistics professors, too. That might just be the ideal background for writing bug reports.

to someone who runs a mail server, the idea of email not getting further than 500 miles is ridiculous and absurd

Not really, unless that someone doesn't know about the structure of networks. My first two hypotheses after reading the problem description were routing anomalies and timeouts.

That other story about the car and vanilla ice cream, on the other hand, is a great example of unintended correlation != causation.

Well, it did involve people with the job title "geostatistician".

Fun article, but I don't completely buy the conclusion. The propagation speed of cat-5, coax and fiber optic cable all fall in the neighborhood of ~60-70% the speed of light in vacuum. Also it's very unlikeliness to have anything resembling a straight line path from the mail server to the destination. If the connections were aborted in a bit over 3ms you would have much shorter range than 500 miles, I'd guess something like 1/4 to 1/2 that distance between the lower propagation speed and indirect path.

The timeout was unlikely to be 3ms. A 100hz clock would give you a timeout of 10ms. Also, the timeout needs to cover the distance in both directions. Half of 10ms is 5ms, which is just about enough for a 60% of c transmission to go 500 miles.

Read the FAQ, linked at the top.

That was a great post and well worth the read.

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