One, you're right, it's nothing to do with Perl. ;)

Two, it's called "daylight saving time" (not savings). You make it sound like a bank where you can withdraw a little extra on a rainy day.

Three, DST in the USA jumps from 2am to 3am (occasionally called the Devil's Hour), or from 2am to 1am (occasionally called the Witch's Hour (not to be confused with the Witching Hour of midnight)).

Four, yes, some versions of the documentation for cron has included such operational notes nearly since its invention. Cron won't fire events for a time which never happened. Cron will fire events twice for times which happen twice.

This is another reason you should update your system time carefully and gradually with ntpd instead of with lurching adjustments like crontab: 11 1 * * * fixtime. If you somehow skip a whole minute, that system backup might not happen.

There are some cron-aids available which can help you. I think one is called anacron. This helps those folks who shut down their computer many nights, or fold their laptops at unpredictable times, but still want a "nightly" backup or a regular database update.

--
[ e d @ h a l l e y . c c ]

In reply to Re: OT: Crontab entry missed due to Daylight savings time? by halley
in thread OT: Crontab entry missed due to Daylight savings time? by freddo411

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