In my opinion you should NEVER use NTPD in a virtual machine.....

Check out how NTPD works... it tries to adjust "software cycles"to "hardware cycles".

"Hardware cycles" are a bit undefined in a virtual machine.

 

Best way, in my opinion, is:

-          Adjust clock of host using NTPD.

-          Adjust clock of virtual machine to clock of host using the appropriate Vritual tools.
(Vmware Tools etc).

 

Regards,

Carel

 

From: [log in to unmask] [mailto:[log in to unmask]] On Behalf Of Zack Yovel
Sent: maandag 30 mei 2011 20:57
To: Alain Péan
Cc: Orion Poplawski; Jaroslaw Polok; [log in to unmask]
Subject: Re: clock drift under Hyper-V

 

 

2011/5/30 Alain Péan <[log in to unmask]>

Le 27/05/2011 18:17, Orion Poplawski a écrit :

	 

	On 05/27/2011 12:14 AM, Jaroslaw Polok wrote:

	Hello
	
	On 05/26/2011 10:28 PM, Orion Poplawski wrote:

	On 05/26/2011 07:29 AM, Zack Yovel wrote:

	
	1. Hyper-V does not support RHEL. The only linux distro it supports is SUSE.

	
	I'm running a couple of CentOS 5.6 instances under Hyper-V.  Horrible clock drift
	issues, but otherwise okay.

	
	You may want to add:
	
	divider=10 clocksource=acpi_pm
	
	to kernel arguments in /etc/grub.conf
	
	to correct the clock drift problem.

	
	Doesn't help me.  Thanks though.  I would have thought that the Hyper-V timesync integration driver would help too, but not for me.

 

Hyper-V does support RHEL, at least 5 (not yet 6 perhaps). See :
http://www.redhat.com/promo/svvp/

But if you have clock drift, why don't you setup an NTP server inside your VM ?

Alain

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As I noted in a different mail, I was wrong and Hyper-V does support RHEL, up to 5.5 (not 5.6, at least according to Microsoft.. http://www.microsoft.com/windowsserver2008/en/us/hyperv-supported-guest-os.aspx perhaps a small difference in 5.6 could cause the problem?).