[CentOS-virt] Time lagging on DomU

Thu Mar 17 16:27:27 UTC 2011
Eric Shubert <ejs at shubes.net>

On 03/17/2011 03:57 AM, Dennis Jacobfeuerborn wrote:
> Hi,
> on one of our systems I see that while the time on the Centos 5.4 Host is
> correct it lags behind on two of the 5.5 guests by almost 5 minutes but is
> correct for the third domU. From what I understand the clock of the system
> is controlled by the host and and guest cannot write to it (and because of
> that not change it). Does anyone now what the cause could be and how I can
> fix the time for the guests?
> Running kernel versions:
> Host (correct time):  2.6.18-164.15.1.el5xen
> guest 1 (correct time): 2.6.18-194.3.1.el5xen
> guest 2 (wrong time): 2.6.18-194.32.1.el5xen
> guest 3 (wrong time): 2.6.18-194.el5xen
> Regards,
>     Dennis

The best way I've found to deal with this is to run ntp server on the 
host, and use ntp on the guests, configured with the host as the ntp 
server. This is what VMware presently recommends as well.

for more, including kernel and ntp settings.

-Eric 'shubes'