NTPD

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Automating the time synchronization

You have two choices for automatic time updating, you can run ntpd all the time as a background process or you can have it run once in awhile (if you are tight on system resources).

Running ntpd all the time

Just enable rc.ntpd script:
chmod +x /etc/rc.d/rc.ntpd
After the script is enabled you probably will want ntpd to start immediately so, can either restart the system or manually start ntpd with:
/etc/rc.d/rc.ntpd start

Running ntpd once in awhile

You have many choices but the two best ones are:
1) Set up a cron job
2) Set up a /etc/rc.d/rc.local entry and update the time on start-up only.
Either way, you need to add the following commands into your cron job or rc.local script:
ntpdate pool.ntp.org <---(updates the time)
hwclock --systohc <------(saves the time to the hardware clock)



Manually updating the time

Issue the following commands:

ntpdate pool.ntp.org
hwclock --systohc



Choosing the right time server

On ntp.org you will find a complete list with the right time server for you. Let's say you live in germany, then you will choose de.pool.ntp.org. A complete List is available at http://support.ntp.org/bin/view/Servers/NTPPoolServers

DST changes

If your time is off due to DST changes, you must update the /etc/localtime file. You should be able to find a correct file on the internet and just replace the old /etc/localtime file.

PROBLEMS

PROBLEM: "Unable to contact time server:" error with KDE's Time Control Module.
FIX: Make sure ntpd is NOT running. If ntpd is running, manual ntp and KDE ntp updates will return errors due to ntpd having control of the ntp port.