Cron

Cron is one of those things I’ve been using for twenty-odd years and still occasionally stare at for thirty seconds before committing. Is */15 9-17 * * 1-5 what I think it is? Does 0 0 * * 0 fire at midnight Sunday or Monday? And does that depend on the box’s timezone or UTC? Most of the time you can squint and reason your way through it, but “most of the time” is exactly the kind of confidence level you don’t want when the cron in question is the nightly DB backup. ...