LinuxQuestions.org
Visit Jeremy's Blog.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - General
User Name
Password
Linux - General This Linux forum is for general Linux questions and discussion.
If it is Linux Related and doesn't seem to fit in any other forum then this is the place.

Notices


Reply
  Search this Thread
Old 06-05-2009, 01:40 PM   #1
jamison
LQ Newbie
 
Registered: Jun 2009
Distribution: CentOS, RHEL, Ubuntu
Posts: 2

Rep: Reputation: 0
Linux on MS Virtual Server clock problems


Apparently this is a known issue, http://support.microsoft.com/kb/918461

From the KB:
---
After you install a Linux-based virtual machine in Microsoft Virtual Server 2005 R2, the system time in the Linux guest operating system runs too fast. For example, the current time in the Linux guest operating system may advance by one minute approximately every 48 seconds. After some time, the Linux-based virtual machine resets the clock to the correct time.
---

I've tried the suggested resolutions in the KB but still having problems keeping my CentOS 5.3 clock accurate. It either runs too fast or too slow. The system clock is inaccurate but the hardware clock seems to stay accurate. Running ntpd does not help because the clock is so far off. I have another CentOS system running on XP with VMware and it does NOT have the same problem.

So what I've done as a solution is to set a cron job which syncs the system clock to the hardware clock every minute.

* * * * * /sbin/hwclock --hctosys

I'm not too happy with this solution and I'm about to deploy a bunch of high traffic web servers using RHEL5 on MS Virtual Server and really want a better fix.

Besides using VMware does anyone have a solid solution?

Does anyone know if this problem also occurs on MS HyperV?

Thanks.
 
Old 06-05-2009, 09:52 PM   #2
TB0ne
LQ Guru
 
Registered: Jul 2003
Location: Birmingham, Alabama
Distribution: SuSE, RedHat, Slack,CentOS
Posts: 21,143

Rep: Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361Reputation: 5361
Quote:
Originally Posted by jamison View Post
Apparently this is a known issue, http://support.microsoft.com/kb/918461

From the KB:
---
After you install a Linux-based virtual machine in Microsoft Virtual Server 2005 R2, the system time in the Linux guest operating system runs too fast. For example, the current time in the Linux guest operating system may advance by one minute approximately every 48 seconds. After some time, the Linux-based virtual machine resets the clock to the correct time.
---

I've tried the suggested resolutions in the KB but still having problems keeping my CentOS 5.3 clock accurate. It either runs too fast or too slow. The system clock is inaccurate but the hardware clock seems to stay accurate. Running ntpd does not help because the clock is so far off. I have another CentOS system running on XP with VMware and it does NOT have the same problem.

So what I've done as a solution is to set a cron job which syncs the system clock to the hardware clock every minute.

* * * * * /sbin/hwclock --hctosys

I'm not too happy with this solution and I'm about to deploy a bunch of high traffic web servers using RHEL5 on MS Virtual Server and really want a better fix.

Besides using VMware does anyone have a solid solution?

Does anyone know if this problem also occurs on MS HyperV?

Thanks.
Nope, sorry. VMware used to have an issue with RedHat and the clock being out of sync, but that was addressed pretty quickly by both parties. I doubt Microsoft cares, and they probably won't fix it for a VERY long time, if at all.

If its any consolation, I had to do the same thing with VMware and RedHat for a month or so, until the patch got released. Thankfully, I was able to keep the synching down to every 15 minutes, instead of every minute.

One thing I will say, is that NTP won't sync up, if the clock is too far out of whack. If you run ntpdate (or sntp, if that command is depreciated on CentOS as it is on OpenSuSE), and get the clock close, you can fire up NTP. The bug exists, though, but you may be able to sync less frequently, and keep NTP running if you get things in synch 'manually'....

Good luck.
 
Old 07-31-2009, 10:56 AM   #3
jamison
LQ Newbie
 
Registered: Jun 2009
Distribution: CentOS, RHEL, Ubuntu
Posts: 2

Original Poster
Rep: Reputation: 0
Just a quick, ironic, and sad update. None of the things I tried would keep the clock accurate to an acceptable level. It's hard to believe but my final solution that works pretty darn good was to install Samba just so that I could run "net time" and sync the clock off of a Windows file server. So a MS solution to a MS problem. Hmm.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Linux Virtual Server (LVS) problems justemail Linux - Newbie 3 06-09-2009 07:03 PM
BYE Clock skew detected. Check the clock on the file server Guardian-Mage Linux - Server 7 04-21-2009 09:48 AM
Virtualmin/Webmin, Postfix, Virtual server.. problems. Devileyezz Linux - Server 0 11-05-2007 08:05 PM
Major problems with hostname, virtual server etc MichaelD Linux - Newbie 1 05-21-2005 08:51 PM
Redhat Linux on Microsoft Virtual Server Problems???? mcostello1 Linux - Hardware 1 09-01-2004 11:14 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - General

All times are GMT -5. The time now is 05:02 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration