Why is my Windows 2008 R2 DC time wrong?

I have a Windows 2008 R2 DC -- which runs as a VMware virtual machine.  I have it configured to an external time source, and the ESX Host/VM sync turned off.  It was brought to my attention yesterday that the domain time was 5 minutes ahead.  I can't figure out why? My configuation is below.  I typed w32tm /resync - and it corrected the time to accurate and has overnight updated everything.  I noted in the Event log that it has been 10 days since it synced, and that it sometimes syncs less frequently than than.  What governs how often it syncs -  and also is the VMTool time sync checkbox  - the only place that time sync between VMWARE Host/VM needs to be turned off?
C Emmons

C:\Windows\system32>w32tm /query /configuration

EventLogFlags: 2 (Local)
AnnounceFlags: 5 (Local)
TimeJumpAuditOffset: 28800 (Local)
MinPollInterval: 6 (Local)
MaxPollInterval: 10 (Local)
MaxNegPhaseCorrection: 172800 (Local)
MaxPosPhaseCorrection: 172800 (Local)
MaxAllowedPhaseOffset: 300 (Local)

FrequencyCorrectRate: 4 (Local)
PollAdjustFactor: 5 (Local)
LargePhaseOffset: 50000000 (Local)
SpikeWatchPeriod: 900 (Local)
LocalClockDispersion: 10 (Local)
HoldPeriod: 5 (Local)
PhaseCorrectRate: 7 (Local)
UpdateInterval: 100 (Local)


NtpClient (Local)
DllName: C:\Windows\system32\w32time.dll (Local)
Enabled: 1 (Local)
InputProvider: 1 (Local)
AllowNonstandardModeCombinations: 1 (Local)
ResolvePeerBackoffMinutes: 15 (Local)
ResolvePeerBackoffMaxTimes: 7 (Local)
CompatibilityFlags: 2147483648 (Local)
EventLogFlags: 1 (Local)
LargeSampleSkew: 3 (Local)
SpecialPollInterval: 3600 (Local)
Type: NTP (Local)
NtpServer: 0.pool.ntp.org,1.pool.ntp.org,2.pool.ntp.org (Local)

NtpServer (Local)
DllName: C:\Windows\system32\w32time.dll (Local)
Enabled: 1 (Local)
InputProvider: 0 (Local)
AllowNonstandardModeCombinations: 1 (Local)

VMICTimeProvider (Local)
DllName: C:\Windows\System32\vmictimeprovider.dll (Local)
Enabled: 1 (Local)
InputProvider: 1 (Local)
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
and also is the VMTool time sync checkbox  - the only place that time sync between VMWARE Host/VM needs to be turned off?

Yes, this is correct, this is the only place, that VMware Tools will sync the time with the host, you can also check in the VM's *.vmx file on the datastore.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
What time source are you using, and have you checked it's accurate and reachable?
Darius GhassemCommented:
Read over this could be a known issue

Determine the Perfect Price for Your IT Services

Do you wonder if your IT business is truly profitable or if you should raise your prices? Learn how to calculate your overhead burden with our free interactive tool and use it to determine the right price for your IT services. Download your free eBook now!

apsutechteamAuthor Commented:
NtpServer: 0.pool.ntp.org,1.pool.ntp.org,2.pool.ntp.org (Local) - these are my External servers.  I see in the Event Log successful syncs -- just not very often - 10-14 days apart.  Also, typing w32tm /resync -- synced the time accurately - shouldn't sync occur more often?  How do I change than?  Also, reading the VM related article - I don't see my problem -- I forget to say I'm running ESX 4.1.  If I have Host/VM time sync turned off - shouldn't virtual time drift not matter?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Checkout this article

Timekeeping in VMware Virtual Machines

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
apsutechteamAuthor Commented:
Article says VMware Tools daemon corrects the guest operating system clock after certain events occur (suspension, snapshots,etc), even if periodic time synchronization is turned off. We had our hosts down recently for new SAN install and new fiber switch install.  I think perhaps VMs synced against hosts -- even though sync is OFF. But if that explains how the time got wrong -- why didn't PDC sync is back -- it last ran on 10/14 -- is that normal. Wouldn't I want it to run more often, and how/where do I set that?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
do you have any other time sync events in the event logs?
apsutechteamAuthor Commented:
Yes. 10/14/2011, 10/1/2011, 9/15/2011,8/11/2011,7/13/2011,6/29/2011,6/15/2011,5/11/2011 ...
Of this message:

Log Name:      System
Source:        Microsoft-Windows-Time-Service
Date:          8/11/2011 3:25:36 AM
Event ID:      35
Task Category: None
Level:         Information
User:          LOCAL SERVICE
Computer:      dc.apsu.edu
The time service is now synchronizing the system time with the time source 0.pool.ntp.org,1.pool.ntp.org,2.pool.ntp.org (ntp.m|0x1|>
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Active Directory

From novice to tech pro — start learning today.