[opensuse] irksome timezone question - dual boot laptop
All, I have a dual-boot laptop I brought on trip from Eastern Standard Time to Pacific Standard Time. After getting to Pacific area I went into Yast and changed my timezone appropriately and double checked it was setup to use ntp. All was good, until yesterday I dual booted into Windows. I didn't pay attention to the time it had, but now I'm back in openSUSE, my clock is off by 4 hours which puts me half way to Japan! What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel. Thanks Greg -- Greg Freemyer Head of EDD Tape Extraction and Processing team Litigation Triage Solutions Specialist http://www.linkedin.com/in/gregfreemyer CNN/TruTV Aired Forensic Imaging Demo - http://insession.blogs.cnn.com/2010/03/23/how-computer-evidence-gets-retriev... The Norcross Group The Intersection of Evidence & Technology http://www.norcrossgroup.com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Greg Freemyer wrote:
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
Configure Windows so that it does not change the hardware clock.
which puts me half way to Japan!
So, how are things on Midway Island? ;-) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Thu, 11 Nov 2010 22:29:27 +0530, Greg Freemyer <greg.freemyer@gmail.com> wrote:
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
i remember reading, during install, that one shouldn't use UTC when also running linux. by default the option is checked, i think. if it's checked in your case, i'd try unchecking it. -- phani. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Thu, 11 Nov 2010 23:05:48 +0530, phanisvara das <listmail@phanisvara.com> wrote:
i remember reading, during install, that one shouldn't use UTC when also running linux.
sorry, meant to say "...when also running windows." -- phani. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Thu, Nov 11, 2010 at 9:35 AM, phanisvara das <listmail@phanisvara.com> wrote:
On Thu, 11 Nov 2010 22:29:27 +0530, Greg Freemyer <greg.freemyer@gmail.com> wrote:
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
i remember reading, during install, that one shouldn't use UTC when also running linux. by default the option is checked, i think. if it's checked in your case, i'd try unchecking it.
Agreed, but that's how it was already. Further delving into the ntp config screen of yast showed the "clock source" it was using was my hardware clock. I changed it to use a ntp server on the net. That's fixed it from linux's perspective for now. I'll worry about windows tomorrow. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
phanisvara das wrote:
i remember reading, during install, that one shouldn't use UTC when also running linux. by default the option is checked, i think. if it's checked in your case, i'd try unchecking it. No. You shouldn't use UTC, if you're dual booting into Windows. Linux handles UTC just fine. It's Windows that messes things up. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thursday, 2010-11-11 at 08:59 -0800, Greg Freemyer wrote:
All,
I have a dual-boot laptop I brought on trip from Eastern Standard Time to Pacific Standard Time.
Intersting problem.
After getting to Pacific area I went into Yast and changed my timezone appropriately and double checked it was setup to use ntp.
All was good, until yesterday I dual booted into Windows. I didn't pay attention to the time it had, but now I'm back in openSUSE, my clock is off by 4 hours which puts me half way to Japan!
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
The typical advice is to set cmos time to local time, so that Windows doesn't have problems, because Linux can use both settings. But when you change timezones, the cmos clock is changed several hours while the other OS is off, and you will have problem regardless of what OS you boot first and which later: the other one will see a time shift. So when you travel and change the local timezone and double boot you have to leave the cmos at UTC (which doesn't change), and tell windows that the cmos clock is UTC. I understand that Windows-7 can do this, others might not (I do not know which version started to allow this). - -- Cheers, Carlos E. R. (from 11.2 x86_64 "Emerald" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.12 (GNU/Linux) iEYEARECAAYFAkzcXWQACgkQtTMYHG2NR9UYGgCdF5NnF0F1ZJDu/8Oav2wrnbOR yOAAn1lPXEEHJLz8+d0HVuK6K3sw8Su8 =n0s2 -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On 11/11/2010 10:59 AM, Greg Freemyer wrote:
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
make sure SuSE is set to use local time *not* GMT. That is a must with dual-boot boxes (or at least it was through vista). Win doesn't understand the hwclock set to GMT so win will always be off by the tzoffset if you set Linux to use GMT. -- David C. Rankin, J.D.,P.E. Rankin Law Firm, PLLC 510 Ochiltree Street Nacogdoches, Texas 75961 Telephone: (936) 715-9333 Facsimile: (936) 715-9339 www.rankinlawfirm.com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On 11/11/2010 11:38 PM, David C. Rankin wrote:
make sure SuSE is set to use local time *not* GMT. That is a must with dual-boot boxes (or at least it was through vista). Win doesn't understand the hwclock set to GMT so win will always be off by the tzoffset if you set Linux to use GMT.
Err, replace GMT with UTC above (although they are the same for all practical purposes, or for that matter, 0 zulu) -- David C. Rankin, J.D.,P.E. Rankin Law Firm, PLLC 510 Ochiltree Street Nacogdoches, Texas 75961 Telephone: (936) 715-9333 Facsimile: (936) 715-9339 www.rankinlawfirm.com -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Thursday, 2010-11-11 at 23:41 -0600, David C. Rankin wrote:
On 11/11/2010 11:38 PM, David C. Rankin wrote:
make sure SuSE is set to use local time *not* GMT. That is a must with dual-boot boxes (or at least it was through vista). Win doesn't understand the hwclock set to GMT so win will always be off by the tzoffset if you set Linux to use GMT.
Err, replace GMT with UTC above (although they are the same for all practical purposes, or for that matter, 0 zulu)
That setting will not work well if you change zones, because there is no zone information in the cmos clock. Think. Europe. Cmos store local time. Fly to New York. Linux. You change the the time zone, not the clock: it is automatic. The changed hour goes to the cmos. Now you boot windows - but windows still thinks in European time, and is off by 6 hours. So you also have to change it. And when you change its time zone it will also change the time again. As I understand, Windows 7 can use the cmos at utc. So I was told, I have to find the setting. - -- Cheers, Carlos E. R. (from 11.2 x86_64 "Emerald" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.12 (GNU/Linux) iEYEARECAAYFAkzdOqUACgkQtTMYHG2NR9UutwCfWyBjC89DRDyZragp7AUwplXu H94AnAiLJs1TV/4Wp8qNT1SyXWQ/MqBB =/1nG -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Fri, Nov 12, 2010 at 5:01 AM, Carlos E. R. <robin.listas@telefonica.net> wrote:
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On Thursday, 2010-11-11 at 23:41 -0600, David C. Rankin wrote:
On 11/11/2010 11:38 PM, David C. Rankin wrote:
make sure SuSE is set to use local time *not* GMT. That is a must with dual-boot boxes (or at least it was through vista). Win doesn't understand the hwclock set to GMT so win will always be off by the tzoffset if you set Linux to use GMT.
Err, replace GMT with UTC above (although they are the same for all practical purposes, or for that matter, 0 zulu)
That setting will not work well if you change zones, because there is no zone information in the cmos clock.
Think.
Europe. Cmos store local time. Fly to New York. Linux. You change the the time zone, not the clock: it is automatic. The changed hour goes to the cmos. Now you boot windows - but windows still thinks in European time, and is off by 6 hours. So you also have to change it. And when you change its time zone it will also change the time again.
As I understand, Windows 7 can use the cmos at utc. So I was told, I have to find the setting.
- -- Cheers, Carlos E. R.
Carlos, You sent me looking and I found: http://weblogs.asp.net/dfindley/archive/2006/06/20/Set-hardware-clock-to-UTC... It provides a registry key to tell windows the hardware clock is UTC. I've just created the key on my Vista install, so I haven't done any testing yet, but I'm rebooting now to set the bios clock and see how things go. If you follow the links you see that with XP it looses sync once or twice a day, which is crazy, so I would avoid doing this trick with XP. With Vista the only issues I found were that some games like flight simulator mess with the hardware clock and expect it to be local time. I don't use this laptop for games, so that's fine with me. I assume Win7 takes the same registry hack. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos,
You sent me looking and I found:
http://weblogs.asp.net/dfindley/archive/2006/06/20/Set-hardware-clock-to-UTC...
It provides a registry key to tell windows the hardware clock is UTC. I've just created the key on my Vista install, so I haven't done any testing yet, but I'm rebooting now to set the bios clock and see how things go.
If you follow the links you see that with XP it looses sync once or twice a day, which is crazy, so I would avoid doing this trick with XP.
With Vista the only issues I found were that some games like flight simulator mess with the hardware clock and expect it to be local time. I don't use this laptop for games, so that's fine with me.
I assume Win7 takes the same registry hack.
Greg
Okay it worked for about an hour! I set the above referenced registry key in Vista, then I rebooted it and all was good. Now an hour later I look down and my current time is showing the UTC time. Not good, but at least its an obvious error. Maybe they have it fixed in Win7 as Carlos has heard. The crazy part is that it seems the basic windows design calls for the user to change their bios clock every time they change timezones. That is just hard for me to believe. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Greg Freemyer wrote:
The crazy part is that it seems the basic windows design calls for the user to change their bios clock every time they change timezones. That is just hard for me to believe.
That goes back to the DOS days, before portable or networked computers. In fact, back in those days, a hardware clock was an option and not built into the motherboard. Back then they were primarily worried about file time & date and not much more. With Linux & Unix, GMT was used from the start, perhaps because it was developed at a telecommunications company, where GMT is commonly used. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Fri, Nov 12, 2010 at 1:01 PM, James Knott <james.knott@rogers.com> wrote:
Greg Freemyer wrote:
The crazy part is that it seems the basic windows design calls for the user to change their bios clock every time they change timezones. That is just hard for me to believe.
That goes back to the DOS days, before portable or networked computers. In fact, back in those days, a hardware clock was an option and not built into the motherboard. Back then they were primarily worried about file time & date and not much more. With Linux & Unix, GMT was used from the start, perhaps because it was developed at a telecommunications company, where GMT is commonly used.
So MS made a bad decision back when Bill Gates was still programming. They knew it was a bad decision the first time someone took a luggable running DOS on a plane. Maybe 1983 or so. It persists today in the FAT filesystem which still uses local time in its date/time fields, but NTFS which came out in the early 90's I think uses UTC, so they've been slowly moving away from that mistake for at least 15 years. And as of Vista (2007?) they still have not fixed it to reliably allow users to have UTC in their hardware clocks. It really is not that hard to fix. Linux has had the "UTC / Local" checkbox for the hardware clock as long as I can remember. And as far as I know, it works reliably. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Greg Freemyer wrote:
So MS made a bad decision back when Bill Gates was still programming.
They made a lot more mistakes than that. ;-) Incidentally, I worked at IBM Canada in the late 90's. In order to to my job (3rd level OS/2 support), I had accounts set up on several different domains across the country. When I logged into a domain in a different time zone, my computer would change to the time for that time zone. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Friday, 2010-11-12 at 21:36 -0500, James Knott wrote:
Greg Freemyer wrote:
So MS made a bad decision back when Bill Gates was still programming.
They made a lot more mistakes than that. ;-)
Incidentally, I worked at IBM Canada in the late 90's. In order to to my job (3rd level OS/2 support), I had accounts set up on several different domains across the country. When I logged into a domain in a different time zone, my computer would change to the time for that time zone.
And some games, like the mentioned Flight Simulator. If you changed the hour of the game, to simulate flying on different conditions, the hour and date of the computer was changed accordingly. - -- Cheers, Carlos E. R. (from 11.2 x86_64 "Emerald" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.12 (GNU/Linux) iEYEARECAAYFAkzeoGAACgkQtTMYHG2NR9URDACgijpHcz2cWddB7sJhNbzVwOqi ZGYAn0y3H+9taZFFpnG+o8yQxkQZl5UH =HGVP -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Friday, 2010-11-12 at 13:54 -0800, Greg Freemyer wrote:
On Fri, Nov 12, 2010 at 1:01 PM, James Knott <> wrote:
date and not much more. With Linux & Unix, GMT was used from the start, perhaps because it was developed at a telecommunications company, where GMT is commonly used.
So MS made a bad decision back when Bill Gates was still programming.
They knew it was a bad decision the first time someone took a luggable running DOS on a plane. Maybe 1983 or so.
Perhaps not, it was IBM. The PC had to ask the user for the time every time it booted. Time zones were not changed, you simply booted and typed the current hour. The machine did not run for long, anyway, and time was unreliable. Using local time was far easier than using UTC and timezones. Consider the OS had less than 360 KiB of disk space, nobody thought that the machine would be such a success and any design decision would have consequences farther away than 5 years. Including the decission to hire MS to do an OS! :-p
It really is not that hard to fix. Linux has had the "UTC / Local" checkbox for the hardware clock as long as I can remember. And as far as I know, it works reliably.
It is probably nearly impossible to change now, because any trivial change affects many functions and third party software. I don't think they see a problem with using local time, even if you travel. You have to change the timezone anyway, the clock is adjusted adequately, and on next boot it works fine. Only people double-booting to linux have problems - so why would they care? - -- Cheers, Carlos E. R. (from 11.2 x86_64 "Emerald" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.12 (GNU/Linux) iEYEARECAAYFAkzd/EMACgkQtTMYHG2NR9UmUACfQMJxqCc0gAXlJNeUjAimE0YS TNkAnA84PlxpaIVSiEoc3NtrUcsDszTH =nZ67 -----END PGP SIGNATURE-----
On Fri, 12 Nov 2010 03:29:27 Greg Freemyer wrote:
All,
I have a dual-boot laptop I brought on trip from Eastern Standard Time to Pacific Standard Time.
After getting to Pacific area I went into Yast and changed my timezone appropriately and double checked it was setup to use ntp.
All was good, until yesterday I dual booted into Windows. I didn't pay attention to the time it had, but now I'm back in openSUSE, my clock is off by 4 hours which puts me half way to Japan!
What is the correct way to have my time set so that both linux and windows get it right and I can bounce between timezones as I travel.
Thanks Greg
Use NTP and set it to point to a public timeserver (e.g. pool.ntp.org). Unfortunately Windows keeps it TZ variable in the registry so automatically updating Windows' TZ variable via a bash script while running Linux is non- trivial. You could always do what I do - boot your Windows partition in VirtualBox from Linux - that way the time is pretty much always in sync. -- =================================================== Rodney Baker VK5ZTV rodney.baker@iinet.net.au =================================================== -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (6)
-
Carlos E. R. -
David C. Rankin -
Greg Freemyer -
James Knott -
phanisvara das -
Rodney Baker