Understand Systemd Timer Units and how to Create them

In this video you will learn to list and manage systemd timer units and additionally create your own so you can really appreciate them. You will learn to list timer units using systemctl list-timers and create new timer units with systemctl edit
Additionally you can find my video courses on Pluralsight: pluralsight.com/training/Autho... and take time to see my own site www.theurbanpenguin.com
00:00 Intro to Timers
01:15 List active timers
02:27 Create timer unit
06:33 Create Service Unit
07:48 Restart systemd and enable the timer
09:54 View timer execution history

[@boubou40]

very instructive, thank you

[@theurbanpenguin]

Thank you

[@brianmurray8943]

I've been watching your pluralsight courses, and I just found your KZbin channel. I can't wait to binge watch this channel! Thank you for dedicating so much of your time to share your knowledge.

[@theurbanpenguin]

Thank you so much Brian

[@Minecrafter_X1]

thank you, very useful. Too many, myself included, rely on crond

[@theurbanpenguin]

Crond is steill very good. I dont think systemd timers will replace user crons, but many services such as logrotate and sysstat now use systemd-timers in place of system cron jobs

[@peterbrown6224]

Curse you! I was supposed to be going to bed. Thanks as well. We didn't lean heavily on systemd at work, and I'm catching up.

[@theurbanpenguin]

Lol

[@r.e.434]

Thanks for explaining, when should I use this instead of cron?

[@theurbanpenguin]

It’s up to you. But many services are moving to systemd. Why would you exact both cron and systemd running. For user crons yes. You need cron running. But for system jobs why would you use a system with no reporting

[@upload-dev]

Can you show how to configure a timer at a random time. I have a script that should be started at least 6 times a day at a random time.

[@theurbanpenguin]

Create the Script: Create your script myscript.sh as before. Create a Timer Unit: Create a systemd timer unit, let's call it random-script.timer. This timer unit will trigger the script exactly 6 times a day at random intervals. Create a file named /etc/systemd/system/random-script.timer and add the following content: ini Copy code [Unit] Description=Random Script Timer [Timer] OnCalendar=*-*-* 00/4:00:00 RandomizedDelaySec=1800 Persistent=true [Install] WantedBy=timers.target In this example: OnCalendar specifies a cron-like expression. *-*-* means every day of the year, and 00/4:00:00 means at every 4-hour interval starting from midnight. RandomizedDelaySec specifies the maximum random delay in seconds before the script is triggered, similar to the previous example. Persistent=true ensures that if the timer is late to trigger due to the system being in sleep mode, it will catch up when the system wakes up.

[@jkg_1]

what is the name of the terminal you are using sir?

[@theurbanpenguin]

I use secureCRT ssh client