Setup Network Time Protocol (NTP) for CentOS

centos_ntp.sh

# setup Network Time Protocol (NTP)
# see http://www.uptimemadeeasy.com/networking/setup-ntp-on-centos-linux/

# check current date/time
date

# setup time zone
mv /etc/localtime /etc/localtime.bkp
cp /usr/share/zoneinfo/Europe/Oslo /etc/localtime

# install NTP
yum install ntp -y
chkconfig ntpd on
cat >> /etc/ntp.conf << EOF
server 0.no.pool.ntp.org
server 1.no.pool.ntp.org
server 2.no.pool.ntp.org
server 3.no.pool.ntp.org
EOF

cat >> /etc/ntp/step-tickers << EOF
0.no.pool.ntp.org
1.no.pool.ntp.org
2.no.pool.ntp.org
3.no.pool.ntp.org
EOF

service ntpd restart
# wait 5-10 minutes and check current date/time again
date