Synchronising Time: CentOS 5.6 virtualised Hyper-V 2008 R2

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Synchronising Time: CentOS 5.6 virtualised Hyper-V 2008 R2

Postby dhirvin » 2011/11/14 15:07:52

Dear fellow users,

We have an instance of CentOS 5.6 running as a virtualised environment on Microsoft Hyper-V 2008 R2.

Is there a way to synchronise the time with the hosting server without refering to our local NTP servers?

The time on hyper-v hosting server is NTP synchronised and correct.

Virtual Microsoft servers all recieve the correct time.

However the virtualised Centos server time is all over the place whether or not synchronised using NTP. We feel NTP should not be used in a virtualised environment as the time should be automatically synchronised wth the hosting server.

Could anyone shed any light on this problem?

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Synchronising Time: CentOS 5.6 virtualised Hyper-V 2008 R2

Postby pschaff » 2011/11/16 19:39:22

Welcome to the CentOS fora. Please see the recommended reading for new users linked in my signature.

I'm not a Hyper-V user, but I believe what you need are the Hyper-V client drivers; however, unfortunately they seem to be problematic for CentOS-5. There is an ELRepo kmod-hyperv for EL6 but not for 5, and the latest ELRepo mainline kernel also does not have them. According to the announcement:
Please note that the Microsoft Hyper-V client drivers have not been
configured for this update. Due to code changes in these experimental
drivers, they currently do not compile in the linux- sources.

One forum thread reported success using "divider=10 notsc" on the GRUB kernel line.

A google on hyper-v centos ~synchronize time OR clock may turn up something else.