I am running a server inside of VMWare, and the clock gains ~30 seconds every 1000 seconds or 1.03X. I need to keep the drift under the magic 1000 limit that ntpd kills its self, but despite setting maxpoll really low I get: Dec 11 23:58:14 host ntpd[4909]: kernel time discipline status change 41 Dec 11 23:59:17 host ntpd[4909]: kernel time discipline status change 1 Dec 11 23:59:17 host ntpd[4909]: time correction of -1123 seconds exceeds sanity limit (1000); set clock manually to the correct UTC time. /etc/ntp.conf: server time.intranet.pdinc.us maxpoll 7 Ideas? If I cannot get ntpd working, then I will have to resort to a cron * * * * * rdate -s time.intranet.pdinc.us -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- - - - Jason Pyeron PD Inc. http://www.pdinc.us - - Sr. Consultant 10 West 24th Street #100 - - +1 (443) 269-1555 x333 Baltimore, Maryland 21218 - - - -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- This message is for the designated recipient only and may contain privileged, proprietary, or otherwise private information. If you have received it in error, purge the message from your system and notify the sender immediately. Any other use of the email by you is prohibited.
> > I am running a server inside of VMWare, and the clock gains > ~30 seconds > every 1000 seconds or 1.03X....> Ideas? If I cannot get ntpd working, then I will have to > resort to a cron * > * * * * rdate -s time.intranet.pdinc.us >ntpdc -p remote local st poll reach delay offset disp =======================================================================time 0.0.0.0 3 64 1 0.00046 -34.34546 7.93799 =LOCAL(0) 127.0.0.1 10 64 1 0.00000 0.000000 7.93752 =time2 0.0.0.0 3 64 1 0.00040 -34.33556 7.93799 =time3 0.0.0.0 3 64 1 0.00050 -34.33738 7.93799 ntpdc -c sysinfo system peer: 0.0.0.0 system peer mode: unspec leap indicator: 11 stratum: 16 precision: -16 root distance: 0.00000 s root dispersion: 0.00099 s reference ID: [0.0.0.0] reference time: 00000000.00000000 Thu, Feb 7 2036 1:28:16.000 system flags: auth monitor ntp kernel stats jitter: 0.000015 s stability: 0.000 ppm broadcastdelay: 0.007996 s authdelay: 0.000000 s But still no clock setting... By the time I wrote the above: st poll reach delay offset disp ====================================== 3 64 37 0.00058 -52.85483 0.43922 10 64 37 0.00000 0.000000 0.43831 3 64 37 0.00034 -52.79517 0.43925 3 64 37 0.00055 -52.80582 0.43925
On 12/12/2007 05:50, Jason Pyeron wrote:> I am running a server inside of VMWare, and the clock gains ~30 seconds > every 1000 seconds or 1.03X. > > I need to keep the drift under the magic 1000 limit that ntpd kills its > self, but despite setting maxpoll really low I get: > > Dec 11 23:58:14 host ntpd[4909]: kernel time discipline status change 41 > Dec 11 23:59:17 host ntpd[4909]: kernel time discipline status change 1 > Dec 11 23:59:17 host ntpd[4909]: time correction of -1123 seconds exceeds > sanity limit (1000); set clock manually to the correct UTC time. > > > /etc/ntp.conf: > > server time.intranet.pdinc.us maxpoll 7 > > Ideas? If I cannot get ntpd working, then I will have to resort to a cron * > * * * * rdate -s time.intranet.pdinc.us > >I would love to see some clear, accurate guidance from anyone regarding time synchronisation within Linux VMs under VMware. From what I've been able to gather, VMware recommend that you disable any in-guest external synchronisation (ntp, windows time etc) and use vmware-tools to sync the time. For now the approach seems to involve trying random kernel boot options and a lot of reboots until you find something that works. I'd be happy to have my understanding of this issue clarified! cheers Luke
On Dec 12, 2007 12:50 AM, Jason Pyeron <jpyeron at pdinc.us> wrote:> I am running a server inside of VMWare, and the clock gains ~30 seconds > every 1000 seconds or 1.03X. > > I need to keep the drift under the magic 1000 limit that ntpd kills its > self, but despite setting maxpoll really low I get: > > Dec 11 23:58:14 host ntpd[4909]: kernel time discipline status change 41 > Dec 11 23:59:17 host ntpd[4909]: kernel time discipline status change 1 > Dec 11 23:59:17 host ntpd[4909]: time correction of -1123 seconds exceeds > sanity limit (1000); set clock manually to the correct UTC time. > > > /etc/ntp.conf: > > server time.intranet.pdinc.us maxpoll 7 > > Ideas? If I cannot get ntpd working, then I will have to resort to a cron * > * * * * rdate -s time.intranet.pdinc.us >Do not use ntp to sync time on the guest OS. Sync using ntp on the HOST, and then use the vmware tools to sync in the guest. I have pursued this issue many times, and that is the best answer. Then update your kernel boot parameters and add: clock=pit # for kernels less than 2.6 OR clocksource=pit # for kernels 2.6.16 and later There is far more than you ever wanted to know about vmware time syncing here: http://www.vmware.com/pdf/vmware_timekeeping.pdf