非常简便:

crontab -e


以下是我的执行过程,输入命令后,会让我选择一个编辑器,我选的是2,因为后边写着easiest,最简单的。

liuyx@myubuntu:/$ crontab -e
no crontab for liuyx - using an empty one

Select an editor. To change later, run 'select-editor'.
1. /bin/ed
2. /bin/nano <---- easiest
3. /usr/bin/vim.tiny
Choose 1-3 [2]: 2
crontab: installing new crontab


选2之后会进入一个文本编辑状态,在里面根据提示,配置你要执行的任务即可:

例如我的配置:

# 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
* * * * * java -jar /home/liuyx/refreshIp/refreshIp.jar


只有最后一行是我写的,我的任务的意思是 每分钟执行一下这个jar包。五个*代表时间规则,后边的就是要执行的命令。命令这个不用说,要执行什么就写什么。时间规则是遵循cron表达式,具体请参阅cron表达式的相关写法。


配置完这些之后,记得执行一下:

sudo service cron restart


来让你的配置生效。


完毕。







也可以参阅这个:https://help.ubuntu.com/community/CronHowto