Howdy, I am having time-drift issues on my CentOS VM. I had referred to following documentation: http://wiki.centos.org/TipsAndTricks/VMWare_Server , however it didn't help. I used kickstart for creating this VM and I am listing important steps in ref to timekeeping issue. Any comments or suggestion would be appreciated. - CS. ------------------- # For EL5 virtual machines, Append the following in Grub to help keep the clock from drifting # and to reduce the interupt requests # 32bit: --append="rhgb quiet divider=10 clocksource=acpi_pm" # 64bit: --append="rhgb quiet notsc divider=10" bootloader --location=mbr --md5pass=$1$mXSD1l6mO$BBCk1gYArAATS7dlCQGthN. --append="rhgb quiet divider=10 clocksource=acpi_pm" %packages --nobase # Other packages not listed here # ntp was installed ntp ### Add step-tickers ### cat > /etc/ntp/step-tickers <<\EOF2 0.centos.pool.ntp.org 1.centos.pool.ntp.org EOF2 ### End of step-ticker file ### -------------------- # Applied patch mentioned on CentOS page # http://wiki.centos.org/TipsAndTricks/VMWare_Server patch --verbose -b -l -i /root/ntp.patch -------------------- VMware Tools not installed. -------------------- Thanks, CS.
Carlos Santana wrote:> Howdy, > > I am having time-drift issues on my CentOS VM. I had referred to > following documentation: > http://wiki.centos.org/TipsAndTricks/VMWare_Server , however it didn't > help. I used kickstart for creating this VM and I am listing important > steps in ref to timekeeping issue. Any comments or suggestion would be > appreciated. > > - > CS. >I'm not sure what version of VMware Server you're running, but I had issues keeping accurate time within guest VMs until I followed the instructions at: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1591 If your guest clocks are running too quickly, this may apply to you. -Greg
On Tue, Oct 13, 2009 at 2:42 PM, Carlos Santana <neubyr at gmail.com> wrote:> Howdy, > > I am having time-drift issues on my CentOS VM. I had referred to > following documentation: > http://wiki.centos.org/TipsAndTricks/VMWare_Server , however it didn't > help. I used kickstart for creating this VM and I am listing important > steps in ref to timekeeping issue. Any comments or suggestion would be > appreciated.The knowledgebase article referenced in the VMWare Server wiki article: http://kb.vmware.com/kb/1006427 is the best source as far as I can tell. This is because VMWare keep the contents up-to-date. As suggested in there, you may want to try the 5.4 kernel -164 (already available for CentOS) without using clocksource or divider= options. This kernel has patches that were offered by VMWare developers to address the time drift issues. Akemi
Carlos Santana wrote:> Howdy, > > I am having time-drift issues on my CentOS VM. I had referred to > following documentation: > http://wiki.centos.org/TipsAndTricks/VMWare_Server , however it didn't > help. I used kickstart for creating this VM and I am listing important > steps in ref to timekeeping issue. Any comments or suggestion would be > appreciated.[..]> VMware Tools not installed.You should certainly install vmware tools, and enable time sync to the guest. Also don't run an ntp server in a Vmware VM. I had an issue on my system running Debian and VMware server, I think it was a hardware/bios issue but the thing was the host system detected the clock speed of the hardware at 1/2 the proper speed. Which caused the host OS clock speed to double. Which wrecked havok in the VMs. Once I loaded the 'p4-clockmod' module that 'fixed' the clock speed in the host and I restarted the guest VMs and things were good after that. Another thing to check is to make sure the 'rtc' driver is loaded, my recent vmware server experience is limited to running it on Debian(have it on 2 systems), so I can't speak to running it on top of CentOS. Most of my ESX guests are CentOS though. Another thing I do is have ntpdate run in cron every so often to do another 'sync' to the host, typically once every 5 minutes I found that in my experience at least there is still some drift over time without doing that even with vmware tools time sync enabled. I do the same on guests running on ESX(roughly 300 of them). I have found on ESX at least, haven't tried any other version of vmware, but on ESX with a VMI enabled kernel(unfortunately none of the RHEL4/5 kernels are VMI-enabled) with paravirtualization you can run an ntp server in the guest. I run dedicated Fedora 8 VMs with ntp servers(my vmware servers sync against those VMs), for this purpose. I know paravirtualization is going away in VMware at some point, hoping to find another solution before that happens. nate
Carlos Santana wrote:> Howdy, > > I am having time-drift issues on my CentOS VM. I had referred to > following documentation: > http://wiki.centos.org/TipsAndTricks/VMWare_Server , however it didn't > help. I used kickstart for creating this VM and I am listing important > steps in ref to timekeeping issue. Any comments or suggestion would be > appreciated. >You want to look at VMware's Best Practices for timekeeping. It says to use Linux's NTP, *not* VMware tools. mark> - > CS. > > ------------------- > # For EL5 virtual machines, Append the following in Grub to help keep > the clock from drifting > # and to reduce the interupt requests > # 32bit: --append="rhgb quiet divider=10 clocksource=acpi_pm" > # 64bit: --append="rhgb quiet notsc divider=10" > bootloader --location=mbr > --md5pass=$1$mXSD1l6mO$BBCk1gYArAATS7dlCQGthN. --append="rhgb quiet > divider=10 clocksource=acpi_pm" > > %packages --nobase > # Other packages not listed here > # ntp was installed > ntp > > ### Add step-tickers ### > cat > /etc/ntp/step-tickers <<\EOF2 > 0.centos.pool.ntp.org > 1.centos.pool.ntp.org > EOF2 > ### End of step-ticker file ### > -------------------- > > # Applied patch mentioned on CentOS page > # http://wiki.centos.org/TipsAndTricks/VMWare_Server > patch --verbose -b -l -i /root/ntp.patch > > -------------------- > > VMware Tools not installed. > > -------------------- > > Thanks, > CS. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >-- The truth will out: someone got it at last: Dogs have masters; cats have staff.
On Tue, 13 Oct 2009, Carlos Santana wrote:> Howdy, > > I am having time-drift issues on my CentOS VM. I had referred to > following documentation:The issue I had with time drift was due to running NTP inside the VM. Don't do it. The VM should get it's time through the VMWare tools that are installed on the guest. Once I did this the drift disappeared. -- James A. Peltier Systems Analyst (FASNet), VIVARIUM Technical Director HPC Coordinator Simon Fraser University - Burnaby Campus Phone : 778-782-6573 Fax : 778-782-3045 E-Mail : jpeltier at sfu.ca Website : http://www.fas.sfu.ca | http://vivarium.cs.sfu.ca http://blogs.sfu.ca/people/jpeltier MSN : subatomic_spam at hotmail.com Does your OS has a man 8 lart? http://www.xinu.nl/unix/humour/asr-manpages/lart.html