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The Largely Untold Story Of How One Guy In California Keeps The World’s Computers Running On The Right Time Zone. (Well, Sort Of)

Down the rabbit hole: my brief odyssey into the esoteric world of the tight-knit time zone data maintenance community who quietly keep the world’s computers from avoiding DST-related-meltdowns

The next time your Linux or MacOS-based computer boots into the perfect time zone, say a mental thank you to Paul Eggert and the team responsible for maintaining the world time zone computer database. Photo by Pixabay from Pexels
If you ever want to know what time zone your computer is configured to in Ubuntu Linux, you can run the ‘timedatectl’ command form the terminal. Screenshot: author.
  • All Linux and Mac-based computers pull their time zones from a massively important database — the time zone database. The process of defining time zones is centralized. This is actually quite a big deal in its own right because people tend to grossly underestimate how pivotal Linux is to … the entire internet and technology as we know it. It may constitute a small percentage of desktop users and be an OS largely favored by nerds and computer developers. But in server-land it’s actually the dominant operating system, especially on the public cloud infrastructure that is rapidly usurping the diminishing role that on-premises infrastructure has to play in getting packets of data from hosts to users (in normal language: making the internet work). AWS instances, for instance, default to Amazon’s Linux spin-off. Virtually all the world’s supercomputers used for everything from weather forecasting to simulating physics experiments run on Linux. Android is a fork of Linux. (I don’t play the “will this be Linux’s year on the desktop?” game. People have been wrong too many times and I don’t particularly care either way). If you’ve ever used an Android device, received a weather forecast, or accessed a website (you’ve probably done all those things), then you’ve benefited from the existence of Linux.
  • The time zone database — which is sometimes called the Olson data or zoneinfo database — has a fascinating history. Unlike most databases, it’s been deemed interesting enough to have a wikipedia entry maintained about it. Just as curiously, the database has also been the subject of litigation. In fact, it’s been deemed so essential to the operation of computers worldwide that ICANN — which approves top level domains (TLDs) among many vital internet-relation functions — has brought it under its auspices. This generally only happens when something is really fricking essential to the internet. Or more accurately, the upkeep of the database is now the responsibility of the Internet Assigned Numbers Authority (IANA) — which sounds vaguely like the sort of organization that would feature either in an Orwell novel, The Martix, or be the go-to name for an intelligence service looking to create complete stultification about what a front company did (“So … what do you for a living.” “Oh, I’m a time zone specialist at the IANA”. *For the sake of clarification: I’m not alleging that either IANA or ICANN is a front company of any intelligence service although that would probably make good fodder for a bad conspiracy theory).

Meet Paul Eggert. The Incumbent Time Zone Coordinator. (TZC). And Where The Buck Totally Stops When Nations Pull Surprise DST Changes. Oh, And Whose Database May Very Well Be Sitting Somewhere On Your Hard Drive.

Paul Eggert, a computer scientist who has led efforts to coordinate time zones on computers for a number of years. Screenshot: UCLA CS department website.



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Daniel Rosehill

Daytime: writing for other people. Nighttime: writing for me. Or the other way round. Enjoys: Linux, tech, beer, random things.