2021-07-21 03:40:13 +00:00
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# Cron
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2021-07-21 03:44:03 +00:00
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An overview of using Ubuntu's built in Cron system.
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2021-07-21 04:06:53 +00:00
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***
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### Edit Cron
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```sh
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sudo nano /etc/crontab
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2021-07-21 03:44:03 +00:00
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```
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2021-07-21 06:55:44 +00:00
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### Auto Update & Upgrade & Reboot/Restart
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```sh
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22 2 * * * root /usr/bin/apt update -q -y >> /var/log/apt/automaticupdates.log
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33 3 * * * root /usr/bin/apt upgrade -q -y >> /var/log/apt/automaticupdates.log
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44 4 * * * root reboot
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```
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***
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# Advanced Configs
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Below is a template/guide to creating your own crontab scripts!
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2021-07-21 04:06:53 +00:00
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### Templates
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```sh
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2021-07-21 03:44:03 +00:00
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[minute] [hour] [day_of_month] [month] [day_of_week] [user] [command_to_run]
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* * * * * root /root/update.sh
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```
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| Field | Values allowed |
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| --- | --- |
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| Minute | 0 to 59 |
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| Hour | 0 to 23 |
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| Day of month | 1 to 31 |
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| Month | 1 to 12 OR JAN to DEC |
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| Day of week | 0 to 6 OR SUN to SAT |
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| Special Syntax | Regular equivalent |
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| --- | --- |
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| @hourly | 0 * * * * |
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| @daily | 0 0 * * * |
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| @weekly | 0 0 * * 0 |
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| @monthly | 0 0 1 * * |
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| @yearly | 0 0 1 1 * |
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