[Novalug] [Dclug] setting time and date (EDT-> EST) i.e. clocks changed

jerry w jerrywone@gmail.com
Sun Nov 1 16:34:21 EST 2009


Yeah, between Halloween (sugar highs),
clocks changing and then elections,
it must be a conspiracy,
disorient people and look for
a new fearless leader/ politician
to save us ;-/

My printer may have figured it out,
but all the wristwatches, microwave,
alarm, stove (forgot VCRS and tvs,
thanks for the reminder)
are even dumber than moi... ;-/

Someone once said If Time Got Hacked,
we'd all be f***ed, and yet every 6 months
or so we try changing everyone's
circadian rhythm, intentionally...
And my sleep is already f*ed
with depression and neighbors.


I'll paste in my offlist message
received to original posting,
with some real tech knowledge
for good measure...

from our offlist friend:
and I learned something
in the last 6 commands
and a little about Zones
too.

Oh, and sorry for x posting...


=======================

Cute.

Although to be completely anal, understand that Zoneinfo already handles
this.  Furthermore, it is highly recommended that all systems use UTC
for the RTC, so you _never_ change the RTC.  From the UTC in the RTC,
the system off-sets using the info in the appropriate Zoneinfo path
(e.g., America/New_York is the official Zoneinfo path for EDT/EST).

Why is this highly recommended?  In addition to never touching the RTC
(other than for adjustments), because different users may set different
off-sets as well, they may have their own off-set as well -- different
than where the physical system is.  ;)

Only Microsoft introduced the concept of setting the RTC to UTC, and
this is still a horrendous default to this day.  That's because Windows
was never designed for the networking and the Internet (something even a
former security head of Microsoft was quoted saying, although he didn't
last much longer after that ;).

As far as commands ...
- hwclock writes to the RTC (often done at shutdown, if not by ntpdated)
- ntpdate** does an one-time NTP client call (e.g., often at boot)
- ntpdated is the resident NTP client (checker) and server

As far as files on Fedora-based systems ...
- /etc/localtime is a copy of the system's Zoneinfo file**
- /etc/ntp/ntpservers are the list of servers used by ntpdate
- /etc/ntp.conf and /etc/ntp/* are used by ntpdated

**NOTE:  ntpdate is now deprecated in favor of "ntpd -q"


--
Bryan J  Smith         Professional, Technical Annoyance

========================

Now, we continue with our regularly
scheduled list programming...
========================

On Sun, Nov 1, 2009 at 2:25 PM, Ed James <edward.james@gmail.com> wrote:
> So one would think - however, I've got two devices, a VCR and a laptop which
> do the switch on the wrong dates - they switch on the dates in vogue some
> years ago, rather than the current switch-dates.  The VCR is hopeless, but
> it'll die eventually.  The laptop is an old P-II, so I run really old
> versions of
> Linux on it.   Yeah, the switch is done automagically - just on the wrong
> day.
>
> Ed James
>
> On 11/1/09, Gregory Maxwell <gmaxwell@gmail.com> wrote:
>> On Sun, Nov 1, 2009 at 5:18 AM, jerry w <jerrywone@gmail.com> wrote:
>>> For those that didn't already set their clocks back,
>>> or are still up overnight,
>>>
>>> su root
>>>
>>> date 11010411
>>
>> Wha!?@#!
>>
>> You shouldn't have to change anything: if your timezone settings and
>> date are correct it'll just change automatically.  You don't even need
>> to be running NTP (which only distributes UTC and knows nothing of
>> daylight savings).
>>
>> (Dozen or so systems changed correctly on their own here; though
>> thanks for the reminder to go check and fix NTP on a few that were
>> pointing at an old address)
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-- 
Jerry W



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