crontab DEMO

cron

# edit crontab job
>crontab -e

[root@localhost shell]# crontab -l
# m     h    d   mon  dow       command  
  0     3    *   *    *  root /bin/sh /data/shell/scan_yuezhi.sh >> /data/shell/output.txt 2>&1 # 每天早晨3点执行
  *     *    *   *    *  root /bin/sh /data/shell/date.sh >> /data/shell/output.txt 2>&1   # 每分钟一次

# scan_yuezhi.sh
#!/bin/sh 

cd /data/projects/project_manager/
/usr/bin/rake pm:scan_tasks RAILS_ENV=production

# date.sh
#!/bin/sh 

/bin/date >> /tmp/date.txt