Is this correct way to set cron for renewal of Let's Encrypt cert in Apache2 ? I use Ubuntu 16.04.
@monthly letsencrypt renew && service apache2 reload
This is a Canonical Question about using cron & crontab.
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The answer for 'Why is my crontab not working, and how can I troubleshoot it?' can be seen below. This addresses the cron system with the crontab highlighted.
When do entries in cron.daily (and .weekly and .hourly) run, and is it configurable?
I haven't found a definitive answer to this, and am hoping there is one.
I'm running RHEL5 and CentOS 4, but for other distros/platforms would be great, too.
(I have already read How can I test a new cron script ?.)
I have a specific problem (cron job doesn't appear to run, or run properly), but the issue is general: I'd like to debug scripts that are cronned. I am aware that I can set up a * * * * * crontab line, but that is not a fully satisfactory solution. I would like to be able to run a cron job from the command line as if cron were running it (same user, same environment variables, etc.). Is there a way to do this? Having to wait 60 seconds to test script changes is not practical.
I schedule some tasks using crontab.
What will happen if my computer is shutdown or turned off during the time when cron was scheduled to do something?
Does each missed cron job run after computer is turned on, or are missed jobs for that day ignored? If missed jobs don't resume, is there any way to configure cron such that it runs the missed tasks after the computer is turned back on?