On Fri, 2008-06-20 at 12:50 +0200, Mertens, Bram wrote: > > -----Original Message----- > > From: redhat-list-bounces@xxxxxxxxxx > > [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of John Horne > > Sent: woensdag 28 mei 2008 0:04 > > To: General Red Hat Linux discussion list > > Subject: Re: Linux server time getting out of sync frequently. > > > > On Tue, 2008-05-27 at 14:50 -0700, Josh Miller wrote: > > > John Horne wrote: > > > >> as i recall, there are a few parameters you can set > > > within the vmware app for the guest os, in order to sync the timing, and to > > stop the skew from occuring... > > > >> > > > >> i think you might also have to modify the kernel startup > > attributes. > > > >> > > > > The only solution I have found to work is to stop NTP on > > the guest and > > > > simply run ntpdate (getting the time from other reliable > > server) every > > > > hour or so via cron. The only 'solution' I have not tried > > is rebuilding > > > > the kernel. Suggestions like use the PIT time source on the kernel > > > > startup line may well improve the timekeeping, but it > > still loses time. > > > > > > Hi, coming into this late, but I have been very successful with the > > > following solution: > > > > > > 1. make sure all ESX hosts are syncing time via NTP with a > > reliable source > > > 2. disable NTPD in all guests > > > 3. set each guest to sync time via VMware tools by setting > > > tools.SyncTime=TRUE > > > 4. in each guest, on the kernel line in grub.conf, set > > clock=pit and reboot > > > > > Tried it, but didn't work. The guests still lost time > > (although the host > > was still accurate). > > I don't know if this is still an issue for you. I haven't seen any > report you got this solved so I thought I'd add our experience. > > A while ago we noticed severely degraded performance on some of our > systems (running WebSphere deployment managers). And also noticed they > were having problems syncing time. The ntpd daemon died just like in > your situation. > > The systems would report 100% CPU usage while on the host system CPU > utilization was close to nihil. Although CPU utilization inside a VM > can not be reliably measured this decrepancy was huge. Our VM > maintainer tried all sorts of tricks - moving the VM back and forth, > trying various options, kernel options and so on to no avail. Then as > the box was originally built on an Intel host but was currently running > on an AMD host the VM was moved back to Intel. At this point both the > host and the VM reported very high CPU usage. After moving back to AMD > again the host reported that the VM was hardly suing any CPU untill we > removed the Vmware tools and reinstalled them. > > So right now everything is back like it was configured before but both > the performance and time syncing issues have been resolved. The only > difference I see is that the vmware tools have now been configure while > the VM was running on the AMD host. > > So perhaps all you need to do is reconfigure the Vmware tools? Perhaps > upgrade to the latest version as well? > In our case the hardware hasn't changed, so reconfiguring the tools would make no difference. John. -- --------------------------------------------------------------- John Horne, University of Plymouth, UK Tel: +44 (0)1752 587287 E-mail: John.Horne@xxxxxxxxxxxxxx Fax: +44 (0)1752 587001 -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
