On Wed, Oct 19, 2022 at 11:20:29PM +0200, Antony Stone wrote:
> On Wednesday 19 October 2022 at 23:16:51, Antony Stone wrote:
>
> > On Wednesday 19 October 2022 at 22:46:54, o1bigtenor via Dng wrote:
> > > How does one set the hardware clock so that it synchronizes with ntp?
> >
> > For me, "/etc/init.d/ntp restart" does the trick (takes a few seconds).
>
> Oh, and I realised you asked specifically about the *hardware* clock - that
> gets done automatically on shutdown.
>
> Do you need to synchronise the *hardware* clock during system run time? I
> can't think of anything which would use that in favour of the kernel clock.
You might want to sync the hardware clock so it's done beforem say, a power failure.
In any case, here's a copy of a web page I downloaded ages ago about time matters.
-- hendrik
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<CENTER><H1>Setting the Date and Time in Linux<BR>
<FONT SIZE=-2>Updated October 10, 2002<BR>
Created September 27, 2000</FONT></H1></CENTER>
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You have at least 2 methods for setting the date and time in Linux:
<OL>
<LI>You can set the time by hand, but be careful, lots of clocks tend to drift over time. The trick here to make the time stick across a reboot is to run the hwclock command as shown below</LI>
<BR>
<LI>You can use NTP (Network Time Protocol) to get accurate time from a network time server (Atomic Clock). I highly recommend using NTP to keep your time set correctly: <A HREF="ntp.html">ntp.html</A></LI>
</OL>
<b class="note">Note: Just using the date command alone will not cause the date to remain after a reboot. The date command sets the Linux system clock which is separate from the hardware clock. The "hwclock --utc --systohc" command is used to update the hardware clock with the date from the Linux system clock.</b><BR>
<BR>
Run the date command to make sure you have the correct time:
<BR><BR>
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[root@server /root]# <B>date</B>
Thu Sep 20 11:00:06 CDT 2001
[root@server /root]#
</PRE>
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<BR>
If you have the wrong timezone set, use "timeconfig" or "linuxconf" to set the correct timezone.<BR>
<BR>
If your timezone is correct but the date and/or time needs updating, the following commands will update the date and time. The second command is needed in order to push the date and time into the PC clock.
<BR><BR>
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<PRE>
[root@server /root]# <B>date 092011082001</B>
Thu Sep 20 11:08:00 CDT 2001
[root@server /root]# <B>hwclock --utc --systohc</B>
[root@server /root]#
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::
Re: [DNG] setting system time
.%0A>%20>%20%0A>%20>%20Oh,%20and%20I%20realised%20you%20asked%20specifically%20about%20the%20*hardware*%20clock%20-%20that%20%0A>%20>%20gets%20done%20automatically%20on%20shutdown.%0A>%20>%20%0A>%20>%20Do%20you%20need%20to%20synchronise%20the%20*hardware*%20clock%20during%20system%20run%20time?%20%20I%20%0A>%20>%20can't%20think%20of%20anything%20which%20would%20use%20that%20in%20favour%20of%20the%20kernel%20clock.%0A>%20%0A>%20You%20might%20want%20to%20sync%20the%20hardware%20clock%20so%20it's%20done%20beforem%20say,%20a%20power%20failure.%0A>%20%0A>%20In%20any%20case,%20here's%20a%20copy%20of%20a%20web%20page%20I%20downloaded%20ages%20ago%20about%20time%20matters.%0A>%20%0A>%20--%20hendrik%0A>%20%0A>%20---------cut%20here---------%0A>%20<!-- CPQLINUX TEMPLATE_HEAD BEGIN - Auto generated, do not edit between matching BEGIN and END sections. -->%0A>%20<HTML>%0A>%20<HEAD>%0A>%20<TITLE>Setting%20the%20Date%20and%20Time%20in%20Linux</TITLE>%0A>%20<LINK%20REV=%22made%22%20HREF=%22mailto:richard.black@cpqlinux.com%22>%0A>%20<META%20NAME=%22author%22%20content=%22Richard%20Black%22>%0A>%20<META%20name=%22keywords%22%20content=%22linux,%20Linux,%20linux,%20Linux,%20compaq,%20Compaq,%20date,%20time,%20timezone,%20tz,%20utc,%20cdt,%20CDT,%20cst,%20CST%22>%0A>%20<META%20name=%22description%22%20content=%22Instructions%20on%20setting%20the%20date,%20time,%20and%20timezone%20in%20Linux%20(and%20making%20it%20stick).%22>%0A>%20%0A>%20<LINK%20REL=%22stylesheet%22%20TYPE=%22text/css%22%20HREF=%22cpqlinux-style.css%22>%0A>%20%0A>%20</HEAD>%0A>%20%0A>%20<BODY%20BGCOLOR=%22#FFFFFF%22%20BACKGROUND=%22generic_background.jpg%22>%0A>%20%0A>%20<CENTER><H1>Setting%20the%20Date%20and%20Time%20in%20Linux<BR>%0A>%20<FONT%20SIZE=-2>Updated%20October%2010,%202002<BR>%0A>%20Created%20September%2027,%202000</FONT></H1></CENTER>%0A>%20<HR>%0A>%20<A%20HREF=%22http://www.cpqlinux.com/sitemap.html%22>Autogenerated%20Site%20Map</A><BR>%0A>%20Search%20this%20Site!:%0A>%20%0A>%20<table%20cellspacing=0%20border=0%20bgcolor=#a0a0a0>%0A>%20<tr><td%20bgcolor=#e0e0e0><font%20size=1%20face=%22arial,helvetica%22%20>%0A>%20<A%20HREF=%22http://search.freefind.com/find.html?id=83840291%22>%0A>%20Search%20this%20site</a>%0A>%20powered%20by%20<A%20HREF=%22http://www.freefind.com%22>FreeFind</A><br>%0A>%20</font></td></tr>%0A>%20<tr><td%20bgcolor=#a0a0a0><font%20size=1%20face=%22arial,helvetica%22%20>%0A>%20<center>%0A>%20<FORM%20ACTION=%22http://search.freefind.com/find.html%22%20METHOD=%22GET%22%20target=%22_self%22>%0A>%20<INPUT%20TYPE=%22HIDDEN%22%20NAME=%22id%22%20SIZE=%22-1%22%20VALUE=%2283840291%22>%0A>%20<INPUT%20TYPE=%22HIDDEN%22%20NAME=%22pid%22%20SIZE=%22-1%22%20VALUE=%22r%22>%0A>%20<INPUT%20TYPE=%22HIDDEN%22%20NAME=%22mode%22%20SIZE=%22-1%22%20VALUE=%22ALL%22>%0A>%20<INPUT%20TYPE=%22HIDDEN%22%20name=%22n%22%20value=%220%22>%0A>%20<INPUT%20TYPE=%22TEXT%22%20NAME=%22query%22%20SIZE=%2220%22>%0A>%20<INPUT%20TYPE=%22SUBMIT%22%20VALUE=%22%20Find!%20%22>%0A>%20<INPUT%20TYPE=%22SUBMIT%22%20NAME=%22sitemap%22%20VALUE=%22Site%20Map%22>%0A>%20</FORM></center></font></td></tr>%0A>%20</table>%0A>%20<HR>%0A>%20<!-- CPQLINUX TEMPLATE_HEAD END - Auto generated, do not edit between matching BEGIN and END sections. -->%0A>%20<!--
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