topic Re: Set Clock in Operating System - Linux

Set Clock

Josh Owings — Wed, 26 Sep 2001 18:51:26 GMT

Can anyone tell me how to set the system time in Red Hat 7.1?
Should I/Can I sync the hardware clock to this new time. If so how would I go about doing so?

Re: Set Clock

Kodjo Agbenu — Wed, 26 Sep 2001 20:14:05 GMT

Hello,

To set system date/time using command-line (as root) :

root@mycomputer# date MMDDhhmm

Where :
MM -> month (01..12)
DD -> day (01..31)
hh -> hour (00..23)
mm -> minute (00..59)

Nobody can't tell you if you should synchronize system time with hardware clock. If you were located on the Greenwitch Meridian Timezone (GMT), I would say : of course yes, you have to do os.

In any other case, I can say : it's up to you.
Some people say that you should set the hardware clock to GMT (also called UTC) and use the TIMEZONE environment variable to specify the time shift between UTC and your local meridian.
For my part, I set hardware clock directly to my local time.

To synchronize hardware clock with system clock (or vice-versa) :

root@mycomputer# hwclock --systohc

To get all options :

root@mycomputer# hwclock --help

Good luck.

Kodjo

P.S. Don't hesitate to assign points to this answer (from 1 to 10).

Re: Set Clock

Josh Owings — Wed, 26 Sep 2001 20:19:10 GMT

That is exactly what I was looking for.
Thank you!

Re: Set Clock

Bernie Vande Griend — Wed, 26 Sep 2001 20:26:56 GMT

Tried to post this earlier, but it crashed on me.

date is great for setting time manually, but ntpd is the way to go to ensure time is always accurate.
You can also use ntpdate to sync time immediately to an ntp server at your site or on the internet.
Example: /usr/sbin/ntpdate -b -s -p 8 ntp-0.cso.uiuc.edu ns.nts.umn.edu harbor.ecn.purdue.edu
This syncs time among 3 internet NTP servers.
If you put servers like these in /etc/ntp.conf and start ntpd then your time should always be accurate.

Re: Set Clock

Josh Owings — Wed, 26 Sep 2001 20:35:17 GMT

Unfortunately the box in question only has internal connectivity at the moment as I am short an NIC card. But, thank you for the reply.