Re: [CentOS] timekeeping on VM - ntpd running

On 11/30/2009 11:34 AM, Jonathan Garden wrote:

This is really stupid question. But referring to: http://lists.centos.org/pipermail/centos/2009-October/083791.html I don't see any line related to ntpd in my /var/log/messages . Do I need to turn-on ntpd for timekeeping on VMs? Some people say not to use ntpd on VMs for timekeeping or is it ntpdate cron job? Can someone please elaborate on this?

On Xen guests, unless /proc/sys/xen/independent_wallclock is set to 1, the DomU will slave itself to the Dom0 clock. So you probably don't need NTP inside the DomU. Our Dom0 uses ntpd to keep itself synchronized with the internal time servers on our LAN.

Whether that is better then using ntpd combined with setting that flag to zero... I'm not sure.