1. Start
1.1. Target: Synchronizing the date in client with server at 6:05 everyday.
1.2. NTP Server: 192.168.1.10
1.3. NTP Client: RHEL 5.8
1.4. Software: crontab
2. Operation in client
2.1. #service ntpd stop
2.2. #chkconfig –level 23456 ntpd off
2.3. #vi /etc/crontab
Ø Source
SHELL=/bin/bash
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root
HOME=/
# run-parts
# 01 * * * * root run-parts /etc/cron.hourly
# 02 4 * * * root run-parts /etc/cron.daily
# 22 4 * * 0 root run-parts /etc/cron.weekly
# 42 4 1 * * root run-parts /etc/cron.monthly
Ø Destination
SHELL=/bin/bash
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root
HOME=/
# run-parts
05 06 * * * root /sbin/ntpdate 192.168.1.10 >> /var/log/date.log 2>&1
# 01 * * * * root run-parts /etc/cron.hourly
# 02 4 * * * root run-parts /etc/cron.daily
# 22 4 * * 0 root run-parts /etc/cron.weekly
# 42 4 1 * * root run-parts /etc/cron.monthly
2.4. #service crond restart
Done.