Jobst Schmalenbach wrote: > Hi. > > I run peridocally (from cron) on all of my machines > > 30 * * * * root /sbin/hwclock --systohc > > All of those machines in question take their time via NTP > from the same local server, and that server gets its time > from a ntp pool. > > Now I had to reboot a couple of them two days ago and to my surprise > all had problems with the time upon booting. > > Here are the important files: > > [root at XXXXXX ~] #>l /etc/adjtime > 0.001687 1289518202 0.000000 > 1289518202 > LOCAL > > [root at XXXXXXX ~] #>l /etc/sysconfig/clock > ZONE="Australia/Melbourne" > UTC=false > ARC=false > > So from my understanding the hwclock should contain the local time. > > [root at XXXXXX ~] #>date > Fri Nov 12 11:26:23 EST 2010 > [root at XXXXXX ~] #>hwclock > Fri 12 Nov 2010 11:26:42 EST -0.167976 seconds > [root at XXXXXX ~] #> > > However on boot I get the following: > > Nov 10 19:08:37 XXXXXX syslogd 1.4.1: restart. > Nov 10 19:08:37 XXXXXX kernel: klogd 1.4.1, log source = /proc/kmsg started. > Nov 10 19:08:37 XXXXXX kernel: Linux version 2.6.18-164.11.1.el5 (mockbuild at builder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4. > 1.2-46)) #1 SMP Wed Jan 20 07:32:21 EST 2010 > Nov 10 19:08:37 XXXXXX kernel: Command line: ro root=/dev/sda2 vga=791 > Nov 10 19:08:37 XXXXXX kernel: BIOS-provided physical RAM map: > ... > ... > Nov 10 19:08:51 XXXXXX kernel: IPv6 over IPv4 tunneling driver > Nov 10 08:08:52 XXXXXX ntpdate[2464]: step time server 192.168.1.1 offset -39599.950905 sec > Nov 10 08:08:52 XXXXXX xinetd[2447]: xinetd Version 2.3.14 started with libwrap loadavg labeled-networking options compiled in. > > and off course dovecot falls over too "Time just moved backwards by 39599 seconds." > > Now, 39600s is 11 hours, which is (inc DST) *MY* offset from Greenwich. > > > So what am I doing wrong? > The idea of running hwclock is to make sure that exactly the problem with dovecot does NOT occur, and ntp does not have a coughing fit when the hardware clock is not close to the correct time upon booting. > The last time I booted some of those machine was more than 200 days ago, so the hwclock will be skewed if I do not update it. > > > Last time I checked the shut down of a machine writes the system time to the H/W prior to reboot. Thus the problem you describe should not occur if proper shutdown occurs. HTH > Jobst > > > > -------------- next part -------------- A non-text attachment was scrubbed... Name: rkampen.vcf Type: text/x-vcard Size: 278 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos/attachments/20101111/08f618a3/attachment-0005.vcf>