Re: [Dovecot] dovecot: Fatal: Time just moved backwards by 3909 seconds.
On 11/30/2009, Udo Rader (list...@bestsolution.at) wrote: The virtual guest is Centos 5.4 based with dovecot 1.2.8 (at first we also tried with the original 1.0.7 (?) dovecot shipped with Centos). I wrote alleged time shift because there is no timeshift whatsoever, or at least I don't notice it anywhere else. ntp is - of course ;-) - up and running and no other applications have time troubles and I've even disabled the local clock as a time reference. Of course you know not to use ntp on VMs, only on the host, right? :) Revent kernels should be able to keep the VM time synced using kvmclock clocksource...
Re: [Dovecot] dovecot: Fatal: Time just moved backwards by 3909 seconds.
Charles Marcus wrote: On 11/30/2009, Udo Rader (list...@bestsolution.at) wrote: The virtual guest is Centos 5.4 based with dovecot 1.2.8 (at first we also tried with the original 1.0.7 (?) dovecot shipped with Centos). I wrote alleged time shift because there is no timeshift whatsoever, or at least I don't notice it anywhere else. ntp is - of course ;-) - up and running and no other applications have time troubles and I've even disabled the local clock as a time reference. Of course you know not to use ntp on VMs, only on the host, right? :) heh, ok, ship hit an sunk :-) I was absolutely not aware of a clocksource kernel parameter, what a weird thing ... Revent kernels should be able to keep the VM time synced using kvmclock clocksource... So I'll give clocksource=acpi_pm a chance and see how it turns out ... Thanks for your hint! -- Udo Rader, CTO http://www.bestsolution.at http://riaschissl.blogspot.com
Re: [Dovecot] dovecot: Fatal: Time just moved backwards by 3909 seconds.
Udo Rader wrote: Charles Marcus wrote: On 11/30/2009, Udo Rader (list...@bestsolution.at) wrote: The virtual guest is Centos 5.4 based with dovecot 1.2.8 (at first we also tried with the original 1.0.7 (?) dovecot shipped with Centos). I wrote alleged time shift because there is no timeshift whatsoever, or at least I don't notice it anywhere else. ntp is - of course ;-) - up and running and no other applications have time troubles and I've even disabled the local clock as a time reference. Of course you know not to use ntp on VMs, only on the host, right? :) heh, ok, ship hit an sunk :-) I was absolutely not aware of a clocksource kernel parameter, what a weird thing ... Revent kernels should be able to keep the VM time synced using kvmclock clocksource... So I'll give clocksource=acpi_pm a chance and see how it turns out ... So for the sake of other peoples' nerves also facing this problem, the solution was to add divider=10 as a kernel boot parameter. There is an good post about this problem here: http://forums.fedoraforum.org/showthread.php?t=211100 and this also leads to this document for VMWare giving an indication of what the suggested parameters for various distributions are: http://kb.vmware.com/kb/1006427 cheers! -- Udo Rader, CTO http://www.bestsolution.at http://riaschissl.blogspot.com
Re: [Dovecot] dovecot: Fatal: Time just moved backwards by 3909 seconds.
On 11/30/2009 4:36 PM, Udo Rader wrote: Recent kernels should be able to keep the VM time synced using kvmclock clocksource... So I'll give clocksource=acpi_pm a chance and see how it turns out ... So for the sake of other peoples' nerves also facing this problem, the solution was to add divider=10 as a kernel boot parameter. There is an good post about this problem here: http://forums.fedoraforum.org/showthread.php?t=211100 and this also leads to this document for VMWare giving an indication of what the suggested parameters for various distributions are: http://kb.vmware.com/kb/1006427 Did you not try the clocksource=kvm-clock? Or do you not have a new enough kernel (2.6.27+)? http://www.proxmox.com/forum/showthread.php?t=2381
Re: [Dovecot] dovecot: Fatal: Time just moved backwards by 3909 seconds.
Charles Marcus wrote: On 11/30/2009 4:36 PM, Udo Rader wrote: Recent kernels should be able to keep the VM time synced using kvmclock clocksource... So I'll give clocksource=acpi_pm a chance and see how it turns out ... So for the sake of other peoples' nerves also facing this problem, the solution was to add divider=10 as a kernel boot parameter. There is an good post about this problem here: http://forums.fedoraforum.org/showthread.php?t=211100 and this also leads to this document for VMWare giving an indication of what the suggested parameters for various distributions are: http://kb.vmware.com/kb/1006427 Did you not try the clocksource=kvm-clock? Or do you not have a new enough kernel (2.6.27+)? http://www.proxmox.com/forum/showthread.php?t=23814 No, unfortunately Centos 5.4 comes with a 2.6.18 kernel (though with many backports from newer versions). % uname -r 2.6.18-164.6.1.el5.centos.plusPAE % cat /sys/devices/system/clocksource/clocksource0/current_clocksource kvm-clock -- Udo Rader, CTO http://www.bestsolution.at http://riaschissl.blogspot.com
