Time is difficult for computers, leap years particularly so

Yesterday was February 29, and yes, things broke. Z Energy, Caltex, and Allied Petroleum network service stations were hit by pay at the pump outages for around 10 hours. The story went around the world and the fuel companies' technology provider Invenco had to scramble to quickly come up with a fix for the issue.

Actually, to be precise, it was February 29 yesterday in New Zealand as we live in the future. Today it's March 1 here, but February 29 in other parts of the world; hold that thought for a moment.

A quick look at the news shows that virtual desktop provider Citrix ran into trouble on leap year day with its HDX video redirection service. It looks like it was the same problem as four years ago, ironically enough.

Some of security vendor Sophos' products could not verify Transport Layer Security (TLS) digital certificates, and users saw alarming error messages. There were a few other glitches, with Japan Today reporting that police in some prefectures were unable to issue driver's licenses due to system errors.

The above examples seem way too few considering how difficult it is for computers to handle time-related issues. Time zones, leap years, daylight savings... ask any coder about the chaos not getting those things right can create, and you'll get some good war stories.

Long story short, computers very much depend on accurate time to sync their clocks with to work properly, which is among other things why we have the Network Time Protocol (NTP) running on Internet-accessible servers.

Here are the NZ NTP pool servers.

Did you see any other Leap Year glitches? Particularly today, elsewhere in the world where it's Feb 29. Let us know in the comments.

This is not particularly technology related, but you have to admire the sheer accidental ingenuity behind La Bougie du Sapeur, a Parisian quadrennial newspaper that was created as an elaborate joke in 1980.

With a price of NZ$8.70 (subscriptions are €100 per century), the paper has print run of 200,000 and a publishing date of February 29. There's a Sunday supplement coming up... in 2032. 

Update

Via Antz in the comments, XKCD has the last word:

Update 2: A representative for Sophos said the security vendor had advised customers that they may experience the above issue if SSL/TLS decryption of HTTPS websites is enabled in the Threat Protection policy and rebooted on February 29, 2024. However, the setting is disabled by default for all users, and would have to be enabled for the problem to occur, the representative said.