Method 1
#tzselect # select timezone e.g. Asia/Shanghai
#echo 'Asia/Shanghai' > /etc/timezone # set timezone
#apt-get install ntpdate # install ntpdate package to synchronize date time
#echo "server 3.cn.pool.ntp.org
>server 3.asia.pool.ntp.org
>server 0.asia.pool.ntp.org" /etc/ntp.conf
#ntpdate -s 3.cn.pool.ntp.org # synchronize date time.
Method 2
#dpkg-reconfigure tzdata
#apt-get install ntpdate # install ntpdate package to synchronize date time
#echo "server 3.cn.pool.ntp.org
>server 3.asia.pool.ntp.org
>server 0.asia.pool.ntp.org" /etc/ntp.conf
#ntpdate -s 3.cn.pool.ntp.org # synchronize date time.
Refrence
ntp pool
HowTo: Linux Server Change OR Setup The Timezone
