使用CentOS7 执行定时脚本，结果提示报错：
/bin/sh: root: command not found
问题在于文件 /var/spool/cron/root ，中无需再写root。
修改之后的脚本：
[root@localhost cron]# crontab -l
*/10 * * * * perl /home/awstats/wwwroot/cgi-bin/awstats.pl -update -config=www.zbphp.com >> /sbin/null 2>&1
文件 /etc/crontab 全部内容：
[root@localhost ~]# nano /etc/crontab
SHELL=/bin/bash
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root
# For details see man 4 crontabs
# Example of job definition:
# .---------------- minute (0 - 59)
# | .------------- hour (0 - 23)
# | | .---------- day of month (1 - 31)
# | | | .------- month (1 - 12) OR jan,feb,mar,apr ...
# | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# | | | | |
# * * * * * user-name command to be executed
查看crontab 状态：
[root@localhost logs]# service crond status
Redirecting to /bin/systemctl status crond.service
crond.service - Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/crond.service; enabled)
Active: active (running) since Sat 2014-10-18 19:13:38 HKT; 31min ago
Main PID: 17467 (crond)
CGroup: /system.slice/crond.service
└─17467 /usr/sbin/crond -n
Oct 18 19:13:38 localhost.localdomain crond[17467]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 56% if used.)
Oct 18 19:13:38 localhost.localdomain crond[17467]: (CRON) INFO (running with inotify support)
Oct 18 19:13:38 localhost.localdomain crond[17467]: (CRON) INFO (@reboot jobs will be run at computer's startup.)
Oct 18 19:24:01 localhost.localdomain crond[17467]: (*system*) RELOAD (/etc/crontab)
Oct 18 19:27:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)
Oct 18 19:32:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)
Oct 18 19:33:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)
Oct 18 19:34:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)
Oct 18 19:38:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)
Oct 18 19:40:01 localhost.localdomain crond[17467]: (root) RELOAD (/var/spool/cron/root)