cron服务每分钟不仅要读一次/var/spool/cron内的所有文件,还需要读一次/etc/crontab,因此我们配置这个文件也能运用 cron服务做一
Ubuntu中
编辑文件 /etc/crontab
sudo vi /etc/crontab
cron服务每分钟不仅要读一次/var/spool/cron内的所有文件,还需要读一次/etc/crontab,因此我们配置这个文件也能运用 cron服务做一些事情。用crontab配置是针对某个用户的,而编辑/etc/crontab是针对系统的任务。此文件的文件格式是:
SHELL=/bin/bash
PATH=/sbin:/bin:/usr/sbin:/usr/bin=
MAILTO=root //如果出现错误,或者有数据输出,数据作为邮件发给这个帐号
HOME=/ //使用者运行的路径,这里是根目录
# run-parts
01 * * * * root run-parts /etc/cron.hourly // 每小时 以root用户身份 执行/etc/cron.hourly内的脚本
02 4 * * * root run-parts /etc/cron.daily // 每天 以root用户身份 执行/etc/cron.daily内的脚本
22 4 * * 0 root run-parts /etc/cron.weekly // 每星期 以root用户身份 执行/etc/cron.weekly内的脚本
42 4 1 * * root run-parts /etc/cron.monthly // 每月 以root用户身份 去执行/etc/cron.monthly内的脚本
注意"run-parts"这个参数,如果去掉这个参数的话,后面就可以写要运行的某个脚本名,而不是文件夹名了。

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