Hi,

This has to have been solved somewhere but apparently
my searchfu is not working well.

I have some windows xp computers which we are syncing
to a time server via ntp. I can see the time server
has the correct UTC time on it and the the PCs are
syncing to the server. I have the time zones set to
GMT on all the PC. The problem is the time is off by 
an hour on all the PCs and I can't figure out why.

Any pointers would be appreciated. I would really like
to just set the PC clocks to UTC but it does not appear
XP has that as an option but GMT should be equivalent
I thought.


thx

Randy

randy wilson wrote:
> syncing to the server. I have the time zones set to
> GMT on all the PC. The problem is the time is off by 
> an hour on all the PCs and I can't figure out why.
> 
> Any pointers would be appreciated. I would really like
> to just set the PC clocks to UTC but it does not appear
> XP has that as an option but GMT should be equivalent
> I thought.

Summer Time /Daylight Savings is currently in operation in the UK.

Could that be the problem, i.e. "GMT" is not fixed?

Is the error that your clocks are one hour ahead?

Terje

-- 
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

Terje Mathisen wrote:

> 
> Summer Time /Daylight Savings is currently in operation in the UK.
> 

In particular, when the Windows timezone setting dialogue says GMT, they 
don't really mean GMT, they really mean UK civil time (or Moroccan, 
depending on the setting).  I think there may be an option to disable DST.

This is basically the result of dumbing down the user interface to match 
the expectations of the general public.

randy wilson wrote:
> Hi,
>
> This has to have been solved somewhere but apparently
> my searchfu is not working well.
>
> I have some windows xp computers which we are syncing
> to a time server via ntp. I can see the time server
> has the correct UTC time on it and the the PCs are
> syncing to the server. I have the time zones set to
> GMT on all the PC. The problem is the time is off by
> an hour on all the PCs and I can't figure out why.
>
> Any pointers would be appreciated. I would really like
> to just set the PC clocks to UTC but it does not appear
> XP has that as an option but GMT should be equivalent
> I thought.
>
>
> thx
>
> Randy

Randy,

Windows, like UNIX, works in UTC internally, as does NTP.  There is no 
need to adjust anything for NTP.  Programs can read the UTC time if they 
wish, and use UTC if they need.

Windows displays the time you choose in the Control Panel, Regional 
settings.  If you want UTC displayed, just choose a time-zone without any 
summer-time adjustment, for example:

  (GMT) Monrovia, Reykjavik

If you have the PCs set to:

  (GMT) London, Dublin, Edinburgh, Lisbon

then during the summer, they will display one hour ahead of UTC, just as 
wall-clocks would.

Cheers,
David 

David J Taylor wrote:
> settings.  If you want UTC displayed, just choose a time-zone without 
> any summer-time adjustment, for example:
> 
>  (GMT) Monrovia, Reykjavik
> 
But make sure that you continually recheck its status.  Tunisia used to 
be in this class, but had DST at very short notice, last year.

David Woolley wrote:
> David J Taylor wrote:
>> settings.  If you want UTC displayed, just choose a time-zone without
>> any summer-time adjustment, for example:
>>
>>  (GMT) Monrovia, Reykjavik
>>
> But make sure that you continually recheck its status.  Tunisia used
> to be in this class, but had DST at very short notice, last year.

Eek!  Why /do/ people have to play with these things?

Any way, perhaps selecting any GMT, and unchecking "Automatically adjust 
clock for daylight saving changes", may also do what the OP wanted.

Cheers,
David 

David J Taylor wrote:
> David Woolley wrote:
>> David J Taylor wrote:
>>> settings.  If you want UTC displayed, just choose a time-zone without
>>> any summer-time adjustment, for example:
>>>
>>>  (GMT) Monrovia, Reykjavik
>>>
>> But make sure that you continually recheck its status.  Tunisia used
>> to be in this class, but had DST at very short notice, last year.
> 
> Eek!  Why /do/ people have to play with these things?
> 
> Any way, perhaps selecting any GMT, and unchecking "Automatically adjust 
> clock for daylight saving changes", may also do what the OP wanted.

On Windows 98 here (GMT) London seems to be BST with an hour
adjustment for DST so turning off DST is always an hour off UTC.
I have timezone set as (GMT) Casablanca, Monrovia. :-)

David

> Cheers,
> David

David Lord wrote:
[]
> On Windows 98 here (GMT) London seems to be BST with an hour
> adjustment for DST so turning off DST is always an hour off UTC.
> I have timezone set as (GMT) Casablanca, Monrovia. :-)
>
> David

That's interesting.  On the Windows-32 systems, London = "GMT" = UTC, and 
having the "Automatically adjust clock for daylight saving changes" 
checked makes the reported time UTC+1 in the summer, and UTC in the 
winter.

Thanks for the heads-up!

David 

David J Taylor <david-taylor@blueyonder.not-this-part.nor-this.co.uk.invalid> wrote:
> David Lord wrote:
> []
>> On Windows 98 here (GMT) London seems to be BST with an hour
>> adjustment for DST so turning off DST is always an hour off UTC.
>> I have timezone set as (GMT) Casablanca, Monrovia. :-)
>>
>> David
>
> That's interesting.  On the Windows-32 systems, London = "GMT" = UTC, and 
> having the "Automatically adjust clock for daylight saving changes" 
> checked makes the reported time UTC+1 in the summer, and UTC in the 
> winter.

Because Windows actually adjusts the CMOS clock when DST begins or ends
(as opposed to keeping the clock in UTC and applying a different offset),
it keeps state information about having done that already.

Therefore, "Automatically adjust clock" is not merely referring to
the automatic change of offset, but to the actual action of changing
the clock setting.  So if you remove that checkmark while DST applies,
it will probably not change your time setting at that instant.  The
clock remains 1 hour ahead because it already was.

David J Taylor wrote:
> David Woolley wrote:
>> David J Taylor wrote:
>>> settings.  If you want UTC displayed, just choose a time-zone without
>>> any summer-time adjustment, for example:
>>>
>>>  (GMT) Monrovia, Reykjavik
>>>
>> But make sure that you continually recheck its status.  Tunisia used
>> to be in this class, but had DST at very short notice, last year.
> 
> Eek!  Why /do/ people have to play with these things?
> 

The politicians do it in an attempt to appear useful!  If you fall for 
it. . . .