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- In this video,

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I want to give you an overview
of task scheduling options.

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It all starts with cron.

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cron is a classical solution.

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It allows you to schedule
reoccurring tasks.

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cron uses the crond daemon,

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and you can use crontab -e to edit tasks.

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And this is what you wanna
do if you wanna make sure

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that the specific task is
happening every hour, day

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or whatever, on a regular basis.

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There's also at.

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at, or at is to learn tasks
once at a specific moment.

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It uses the atd daemon,
and you use the at command

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to schedule the tasks.

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The third way is the systemd timer.

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As you know, systemd
is taking over a lot of

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functionality that previously
was done by other solutions.

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And the systemd timer is the
newer alternative to cron.

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It works by creating a .timer unit,

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and you run this timer
unit using systemctl.

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So what do you remember
about this, when to use what?

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Well, I would advise, as a
generic solution go for cron.

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It's old it's proved and
everybody is using it.

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So there's nothing wrong with it.

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systemd timers, you
need to be aware of them

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because as systemd is becoming
more and more important

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you will see an increasing
amount of systemd timers,

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and you will also see that
chron jobs are being replaced

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by systemd timer jobs,

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especially in the operating system itself.

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at, is not that important.

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at is important for users
that want to run a task

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at a specific moment, and once only.

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But most of the cases you'll
be dealing with cron anyway.