I will use this article to collect interesting tips and tricks about using the Linux cron. This is not so much about setting up a cron, but about little things I use or discovered!
The cron daemon is a long-running process that executes commands at specific dates and times. You can use this to schedule activities, either as one-time events or as recurring tasks.
For commands that need to be executed repeatedly (e.g., hourly, daily, or weekly), you can use the crontab command. The crontab command creates a crontab file containing commands and instructions for the cron daemon to execute.
Format is: MIN HOUR DOM MON DOW CMD
Minute field
Hour field
Day of month
Day of week
Command
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crontab -l # Viewing the cronjobs as currently logged in user crontab -e # Edit the cronjob for currently logged in user crontab -l -u $USER # View the cronjob for the specified user crontab -e -u $USER $ Edit the cronjob for the specified user |
Run every 5 minutes
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*/5 * * * * /home/reggaenights/script.sh |
Run yearly, monthly, weekly, daily or on reboot.
@yearly will run at 00:00 on Jan 1st for every year.
@monthly will run at 00:00 on 1st of every month.
@weekly will run at 00:00 on starting of every week.
@daily will run at 00:00 on every day.
@reboot will run after the server has been rebooted
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@yearly /home/reggaenights/script.sh @monthly /home/reggaenights/script.sh @weekly /home/reggaenights/script.sh @daily /home/reggaenights/script.sh |
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*/30 * * * * /bin/bash /cleanup | /usr/bin/mail -s "Notify me" your@email.org |
A real cron does not rely on website activity and executes independently.
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*/30 * * * * /usr/bin/wget -q -O - https://yourwordpress.org/wp-cron.php?doing_wp_cron |
Do not forget to disable the virtual WordPress Cron in the wp-config.php!
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define('DISABLE_WP_CRON', true); |
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*/30 * * * * /usr/bin/wget -q -O - https://yourcrone.org/wp-cron.php?doing_wp_cron >/dev/null 2>&1 |
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# Email to send output to MAILTO="a@b.com,b@b.com" # Setup your path for reuse PATH="/usr/bin:/sbin:/bin" # Tells which directory the cron should execute the crontab commands from HOME="/path/to/app/root" #Set the default shell SHELL="/bin/bash" |
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*/15 * * * * /home/reggaenights/script.sh >> /home/collect/cron/output/pipe.log 2>&1 |
Ich bin ein Full-Stack-Entwickler. Meine Expertise umfasst:
Ich liebe die Entwicklung, das Design und kenne mich auch mit Serverarchitekturen aus. Ich würde mich nie vollständig fühlen, wenn einer der Bereiche fehlen würde.
Ich habe ein breites Interessengebiet, deshalb tauche ich ständig in neue Technologien ein und erweitere mein Wissen, wo immer es nötig ist. Die Technologien entwickeln sich schnell und ich genieße es, die neuesten Technologien zu nutzen.
Abgesehen davon bin ich ein friedliebender Kerl, der versucht, Leute um sich herum zu haben, die dasselbe denken. Ich glaube wirklich an das Prinzip: "Wenn man jemandem hilft, wird einem jemand helfen, wenn man es braucht."