cp -rf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime;yum install -y ntp ;yum install -y ntpdate;whereis crontab;yum install -y crontabs


crontab -e
00 04 * * * /usr/sbin/ntpdate us.pool.ntp.org;/sbin/hwclock -w;


service crond restart;