Ubuntu 14.04 定时任务

Posted 2021-01-12 F

如何在Ubuntu上启动一个定时任务，使得可以定时删除机器上的日志

首先，

#查看cron状态

service cron status

 

如果提示没有安装

#安装cron服务

apt-get install cron

 

如果提示正在运行

#编辑当前用户的计划任务文件
crontab -e 

 

弹出编辑界面，如下文件，加入最后一行代码，意思是每两分钟向/home/cron_test文件写入一次Hello World

# 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
*/2 * * * * echo "Hello World" >> /home/cron_test 

　　

CTRL+x 退出，此时提示是否保存，输入yes,然后回车

#重载cron

sudo service cron reload

 

#显示当前用户的计划任务文件
crontab -l 

此时会弹出当前用户的计划任务的文件内容

 

#重启cron服务

sudo service cron restart

 

然后tail -f /home/cron_test,将会每两分钟显示一次Hello World

 

结束~~