本文将教您如何安排玉米作业，以便每天在特定时间执行脚本，命令或Shell脚本。作为系统管理员，我们知道在后台自动运行例行维护作业的重要性。Linux corn实用程序将帮助我们维护这些作业以在后台运行。
MIN HOUR Day of month Month Day of Week Command 0-59 0-23 1-31 1-12 0-6 Any Linux command or script
要查看机器上存在的cron作业列表，请运行以下命令–
# crontab -l no crontab for root
要添加新的cron作业，请运行以下命令–
#crontab -e no crontab for root - using an empty one Select an editor. To change later, run 'select-editor'. 1. /bin/ed 2. /bin/nano <---- easiest 3. /usr/bin/vim.basic 4. /usr/bin/vim.tiny Choose 1-4 [2]:2 # Edit this file to introduce tasks to be run by cron. # # Each task to run has to be defined through a single line # indicating with different fields when the task will be run # and what command to run for the task # # To define the time you can provide concrete values for # minute (m), hour (h), day of month (dom), month (mon), # and day of week (dow) or use '*' in these fields (for 'any').# # Notice that tasks will be started based on the cron's system # daemon's notion of time and timezones. # # Output of the crontab jobs (including errors) is sent through # email to the user the crontab file belongs to (unless redirected). # # For example, you can run a backup of all your user accounts # at 5 a.m every week with: # 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/ # # For more information see the manual pages of crontab(5) and cron(8) # # m h dom mon dow command
添加以下示例，每天在11:00执行指定的日志备份Shell脚本。我们可以在一个字段中指定逗号分隔的值，该字段指定脚本需要在所有提到的时间内执行。
00 11 * * * /home/backups/scripts/log_backup.sh
结论：在配置结束时，您可以每天在特定时间运行脚本或命令，这样我们可以使用逗号分隔值指定多次执行的时间。