Comment by gchamonlive

3 hours ago

Moved from cronie to systemd timers because they are resilient to system startup times. My backup strategy is to create a borg archive entry every day at a fixed time. With cronie the system needs to be running at the scheduled time, but systemd timer tolerates this and runs the service as soons as the system is available.

Btw this is my repo for the backup automation: https://github.com/gchamon/borg-automated-backups

14 comments

gchamonlive

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mid-kid  2 hours ago

Cronie has a mechanism for this, called "anacron", which is called hourly by cron (on my system, /etc/cron.hourly/0anacron), and performs all the /etc/cron.{daily,weekly,monthly} tasks, no matter if the earliest possible schedule was missed (and with a configurable random delay). You can modify /etc/anacrontab to create custom schedules.

To do this at the user level, you can add something like "@hourly anacron -t /path/to/anacrontab -S /path/to/spooldir" to the user's crontab, though I've never tried this.

Many cron implementations have a similar mechanism.

  • gchamonlive  1 hour ago

    EDITED

    This isn't the same as with systemd timer because timer lets you specify when you want to run your service exactly and will fallback to running when the system comes online. With @hourly I lose this control and multiple machines could potentially trigger backups at the same time, hogging the physical hard drives and the network.

    • layer8  1 hour ago

      Cron also has @reboot. Not exactly the same, but has been sufficient for me so far.

    • newsoftheday  1 hour ago

      > fallback to running when the system comes online.

      That isn't something I'd want to happen, it sounds like it creates a potential queue of scripts that will flood the system on start, if it works the way you described.

      I prefer the deterministic behavior of cron, the script will run when it is specified to run, as you said earlier, as long as the system is running; and as I stated in a separate comment, it will run @reboot if I need it to run then.

      > With @hourly I lose this control and multiple machines could potentially trigger backups at the same time

      Then don't use @hourly, use staggered times, it's very easy.

      5 replies →

newsoftheday  1 hour ago

I'm sorry, I tried Googling the word "tolates" but I can't find any definition that makes sense?

> runs the service as soons as the system is available.

cron has the @reboot option which I use for a few scripts and works great.