dmesg: Invalid time in clock: check and reset the date
Hi, I've just installed FreeBSD 7.0 Release along with Windows XP on my PC. I found that when I set the clock to the correct time&date, next time I boot into FreeBSD it changes and reports the wrong time&date. Both BIOS and Windows reports the time correctly. dmesg shows the following message: Invalid time in clock: check and reset the date! Can't figure out what's wrong... any help will be appreciated. regards ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: dmesg: Invalid time in clock: check and reset the date
Richard Smith wrote: Hi, I've just installed FreeBSD 7.0 Release along with Windows XP on my PC. I found that when I set the clock to the correct time&date, next time I boot into FreeBSD it changes and reports the wrong time&date. Both BIOS and Windows reports the time correctly. dmesg shows the following message: Invalid time in clock: check and reset the date! Can't figure out what's wrong... any help will be appreciated. Is the time out by an exact number of hours?[*] Does the offset correspond to your localities' timezone offset from UTC? If so, then what is happening is this: Windows will only deal with one timezone at a time, and it expects the system clock (and consequently the CMOS clock on the motherboard) to be set to the local wall-clock time. Unix in comparison allows each process to be run in an arbitrary timezone, simply by setting the TZ environment variable. It expects the system clock and the CMOS clock to be set to UTC, and it calculates the local offset as required. When you reboot the machine, the internal system clock is set from the cmos clock, so one or the other OS will end up thinking local wall-clock time is UTC or vice-versa. Unless you have the happy fortune to be living in this Sceptered Isle (but only during the wintertime), or in certain parts of West Africa that's going to cause problems. If you need to dual-boot, FreeBSD provides a mechanism for allowing the CMOS clock to be set to wallclock time. You can toggle the setting using /usr/sbin/tzsetup -- if there is a zero length file /etc/wall_cmos_clock then your system is running in compatability mode. Note: this file should not appear on a box that is dedicated to running FreeBSD[+] -- the tzsetup default is the /wrong/ choice in this case. Cheers, Matthew [*] Assuming you don't live in Newfoundland or one of the other odd places with timezones that have a 30 minute offset. [+] or that only dual boots to *BSD or Linux or MacOS X or Solaris etc. -- Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard Flat 3 PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate Kent, CT11 9PW signature.asc Description: OpenPGP digital signature
RE: dmesg: Invalid time in clock: check and reset the date
> -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of Matthew Seaman > Sent: Saturday, October 11, 2008 12:49 AM > To: Richard Smith > Cc: freebsd-questions@freebsd.org > Subject: Re: dmesg: Invalid time in clock: check and reset the date > > > Richard Smith wrote: > > Hi, I've just installed FreeBSD 7.0 Release along with Windows > XP on my PC. I found that when I set the clock to the correct > time&date, next time I boot into FreeBSD it changes and reports > the wrong time&date. Both BIOS and Windows reports the time correctly. > > > > dmesg shows the following message: > > Invalid time in clock: check and reset the date! > > > > Can't figure out what's wrong... any help will be appreciated. > > Is the time out by an exact number of hours?[*] Does the offset > correspond to your localities' timezone offset from UTC? > > If so, then what is happening is this: Windows will only deal with > one timezone at a time, and it expects the system clock (and > consequently the CMOS clock on the motherboard) to be set to the > local wall-clock time. > > Unix in comparison allows each process to be run in an arbitrary > timezone, simply by setting the TZ environment variable. It > expects the system clock and the CMOS clock to be set to UTC, and > it calculates the local offset as required. > > When you reboot the machine, the internal system clock is set from > the cmos clock, so one or the other OS will end up thinking local > wall-clock time is UTC or vice-versa. Unless you have the happy > fortune to be living in this Sceptered Isle (but only during the > wintertime), or in certain parts of West Africa that's going to > cause problems. > > If you need to dual-boot, FreeBSD provides a mechanism for allowing > the CMOS clock to be set to wallclock time. You can toggle the > setting using /usr/sbin/tzsetup -- if there is a zero length file > /etc/wall_cmos_clock then your system is running in compatability > mode. Note: this file should not appear on a box that is dedicated > to running FreeBSD[+] -- the tzsetup default is the /wrong/ choice > in this case. > No, it's not. There is nothing wrong with running the CMOS clock on wall-clock time even on a dedicated system. You can do it any way you please. Any real server should be synced by NTP in any case since the internal RTC clock chip in a PC is not reliable or accurate. Note that if you do run the CMOS clock on UTC that if your BIOS/CMOS has a fancy auto-adjusting daylight savings time thingie in it, you should disable that. Ted ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"