https://blog.csdn.net/frank_ldw/article/details/81219289
https://blog.csdn.net/qq_34206560/article/details/80900729
https://blog.csdn.net/xy707707/article/details/80938231
https://www.cnblogs.com/xd502djj/p/4292781.html
crontab -e
30 23 * * * bash some.sh >> some.log
sudo cat /var/log/cron.log
注：Ubuntu 默認沒有開啟cron log.
在/etc/rsyslog.d/50-default.conf文件中取消#cron.* /var/log/cron.log注釋符號#， 并重啟rsyslog sudo service rsyslog restart
