1、查看时间和时区
Logged in as root, check which timezone your machine is currently using by executing `date`. You’ll see something like Mon 17 Jan 2005 12:15:08 PM PST, PST in this case is the current timezone.
2、找到所有系统可用的时区设置，子目录下面也有
Change to the directory /usr/share/zoneinfo here you will find a list of time zone regions. Choose the most appropriate region, if you live in Canada or the US this directory is the “America” directory.
3、备份当前时区设置
If you wish, backup the previous timezone configuration by copying it to a different location. Such as
mv /etc/localtime /etc/localtime-old
4、创建新的时区，软连接
Create a symbolic link from the appropiate timezone to /etc/localtime. Example:
ln -sf /usr/share/zoneinfo/Europe/Amsterdam /etc/localtime
5、同步时间，同步服务器列表可以去google
If you have the utility rdate, update the current system time by executing
/usr/bin/rdate -s time.nist.gov
6、开机的时候设定时区
Set the ZONE entry in the file /etc/sysconfig/clock file (e.g. “America/Los_Angeles”)
7、把系统时间写入bios硬件
Set the hardware clock by executing:
/sbin/hwclock –systohc