LVS
lvs-users
Google
 
Web LinuxVirtualServer.org

Re: clock constantly out of sync

To: "LinuxVirtualServer.org users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: clock constantly out of sync
From: Sebastiaan Veldhuisen <seppo@xxxxxxxxxx>
Date: Thu, 17 Nov 2005 13:12:36 +0100
On Thu, 2005-11-17 at 10:56 +0100, Leon Keijser wrote:
> > Guy (and hopefull girls),
> > 
> > This has nothing to do with LVS and/ or heartbeat. I guess you are 
> > running a Linux guest within a Linux host vmware server (or 
> > ESX)? If so, 
> 
> Yup, ESX.
> 
> > - On the  VMWare Server management console webinterface, go 
> > to Options , 
> > Advanced Settings, and search fro the option  Misc.TimerHardPeriod. 
> > Default value is 1000 , adjust it to 333.
> 
> I'm guessing this will affect all virtual servers?

Yes it does.

> 
> > On the linux  guest machine:
> > 
> > -For Grub edit: /boot/grub/menu.lst  add "clock=pmtmr" to add 
> > the end of 
> > your current kernel and reboot.
> 
> I did (without doing the first) and this already looks promising. Heartbeat
> now says every 5 minutes (in syslog) that it has compensated because the
> clock jumped backwards, but i guess this is okay.
> 
> Btw, the kb on vmware.com said the same, except forgot to mention that this
> is a kernel parameter. So they advised to put this line at the end of
> grub.conf  ... hmpf

Good to know. You still get minimal time fluctuations. For our setup,
this was acceptable.

> 
> > -This should fix your problem (run ntpd on both host and guest OS, no 
> > vmware-tools)
> 
> Hm, but somebody else just advised against using ntpd, and recommended
> ntpdate. 

Well, you have totest this for yourself. Our results showed that we get
better results with ntpd insteda of ntpdate.

> 
> > More info on this issue (not appropriate fix though):
> > 
> > http://www.vmware.com/support/kb/enduser/stdadp.php?pfaqid=1339
> >  http://www.vmware.com/support/kb/enduser/stdadp.php?pfaqid=1420  
> > https://www.vmware.com/community/thread.jspa?forumID21&threadI
> > D13498&messageID=138110#138110 
> > H 
> > https://www.vmware.com/community/thread.jspa?forumID21&threadI
> > D16921&messageID=185408#185408  
> > http://www.vmware.com/support/kb/enduser/stdadp.php?pfaqid=1518
> > 
> > Regards,
> > 
> > Sebastiaan Veldhuisen
> > Arsenso
> > Artistic, Sensible and Sound
> > www.arsenso.nl
> 
> dank u!
> 
> 
> Léon

Your welcome :)

regards,

Sebastiaan


<Prev in Thread] Current Thread [Next in Thread>