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Mc2102Flag for United States of America

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Time Sync issues Winows Server 2008

Hello,

I am working on this issue for a while now and I am not able to get to the bottom of my problem. I really hope someone can help.

I have two ESXi 4.1 hosts which run several VMs. I lately discovered that no matter which VM i start that the time is completely off. Not a litte about 7 hours backwards. It does not matter if I restart a DC - even the PDC, a member server or a stand alone server. All of them start with the wrong time. I just added for example a new member server and if it starts the time is 7 hours behind. I have to sync the time with the w32tm /resync command or restart the time service otherwise the time does not sync. I added this standalone server to the domain and the same issue. But the DC is acting as a reliable time source.
I also checked that the VMs do not sync their times with the ESX host. No errors in the Event Logs after the restart. Where do these VMs get the wrong time from? Or what do they sync their time with?

Can anybody please help because I am pulling my hair out over this issue.

Thank you
Mc2102
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coolsport00
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Have you configured an ATS in your domain? http://support.microsoft.com/kb/816042
If so, configure your ESX/i hosts to point to this server; make sure your VMs (as it seems you have) do not sync with the host in VMware Tools. Your VMs should then get time from the DC they authenticate with, as DCs get their time from the ATS.

Hope that helps.

~coolsport00
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ASKER

Hello,

I think I might have found something. I just booted one of the VMs and started into its BIOS and then time in there is matching the wrong time in the OS. Ok then I know now where the VMs get the incorrect time from but now the question is why are do the VMs have the wrong time in their BIOS. Are they syncing their time with the ESX host? I changed the time in the BIOS of the VM to the correct time but as soon I restarted the VM the time is off again.

Thank you
Mc2102
Is VMware Tools of this VM set to sync with the host? Have you configured your ESX host to sync with your domain's ATS?

~coolsport00
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JRoyse
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Also, here are some pretty good articles that discusses time sync'ing in more detail:
http://kb.vmware.com/kb/1318
http://www.vmware.com/files/pdf/Timekeeping-In-VirtualMachines.pdf

Regards,
~coolsport00
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JRoyse might have got me the right idea. I have two ESXi 4.1 hosts and I checked the time server configuration and on one there was none at all and on the other one there where the DC configured as the NTP source. I am not to sure if that is such a good idea so I configured both ESXi hosts to point to a external NTP server - the same the PDC is pointing to and now the VMs seem to start with the correct times. But I want to do some more testing before I party. I will keep you guys updated.
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I fixed the NTP settings on the ESXi hosts and after they synced their time correctly with the NTP server the VMs also had the right time and all my issues went away.