[CentOS] system time automatically fowards in time and then comes back to normal

[Alexander Dalloz]

Benjamin Franz schrieb:
> nate wrote:
>> Akemi Yagi wrote:
>>   
>>> for VMware products including ESX and ESXi.  According to their
>>> current recommendations, " In all cases use NTP instead of VMware
>>> Tools periodic time synchronization."
>>>     
>> I've been using vmware for 10 years, and I've never, ever ever
>> gotten NTP to hold sync inside of a VM outside of using a VMI
>> enabled kernel.
>>   
> 
> I've got more than 20 VMs spread over 5 machines (VMware Server 2.x), 
> both 32 and 64 bit (hosts and VMs) that hold time perfectly using NTP.
> 
> 1) Make *SURE* that 'cpuspeed' and any BIOS 'power saving' modes are 
> disabled on your host and your VMs. Nothing screws timekeeping like 
> having the CPU speed vary.
> 
> 2) Use 'divider=10' on your grub kernel boot lines for your virtual 
> machines.

That kernel parameter information is out of date with CentOS 5.4:

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1006427

As Akemi said, users of VMware virtualization products (bare metal
hypervisor products like ESX/ESXi and the other solutions) should
closely follow the KB article recommendations which are frequently updated.

Alexander