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SME 7.3 as VMWare guest losing Time - opinions

Offline dvdsmith

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SME 7.3 as VMWare guest losing Time - opinions
« on: July 11, 2008, 06:06:47 PM »
Before anyone responds, yes I search the forums, bugzilla and wiki.  I would post this to Bugzilla, but the consensus seems to be it is a VMWare problem.  Also, I'm not talking about the VMWare contrib, but a fresh SME 7.3 install as a guest O/S on a VMWare Server (running on Windows 2003).  I think I've solved the problem, but I thought I'd post this both to see if there are consequences I'm unaware of and to possibly help others with the same issue.

I've found a number of posts regard time issues with SME as a guest on a VMWare server, but most seem to deal with time running fast.  In my case it was losing time somewhere around 10-20 seconds per minute.  Of the different forum threads, the solution posted by mmccarn at the following link; http://forums.contribs.org/index.php?topic=32139.0  in the Legacy Forums seems to have solved the issue. 

Unsuccessful suggestions included;

* Adding "clock=pit" in /boot/grub/grub.conf had no effect.  Some posts and bugs said to add "clock=pic".  Correct me if I'm wrong but I think this is a typo as I can't find a reference to it anywhere outside contribs.org.

* Install VMWare-Tools.  While this did have some success, it introduced more problems.  I installed VMWare-tools on a fresh 7.3 install.  Everything seemed fine until I ran "yum --enablerepo=contrib update", then I lost my NIC.  This appears to be a problem with SME 8.0 as well, see http://bugs.contribs.org/show_bug.cgi?id=3482.  Also, I dislike this solution because its another process running on my server for which I need for only one of its features.  My current solution is way less involved and doesn't require access to the VMWare Server, but only an ssh session to the SME Server.

Interestingly, I found a reference to a problem similar to mine on the CactiEZ forum, which also runs on CentOS. Here is the link; http://forums.cacti.net/about21606.html 

Well, anyone have an opinion?  Am I way off the mark anywhere?

Thanks,

DVDSmith

« Last Edit: July 11, 2008, 06:11:44 PM by dvdsmith »

Offline cactus

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Re: SME 7.3 as VMWare guest losing Time - opinions
« Reply #1 on: July 11, 2008, 06:41:38 PM »
Well, anyone have an opinion?  Am I way off the mark anywhere?
These are general problems with the 2.4.x linux kernel releases, and are oin a very low level in clock pulse frequencies set during kernel compilation. It is in the vmware documentation somewhere.

I believe bot host and guest should have the clock=pit set to have things working. More technical details are here: http://www.vmware.com/pdf/vmware_timekeeping.pdf (page 11 and 12 deal with the linux timing issues).

Also have a look at this one: http://www.synapticsolutions.com.au/?page_id=28 , which you should have found in the forums as I have posted it multiple times (already).
« Last Edit: July 11, 2008, 06:43:34 PM by cactus »
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Offline arne

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Re: SME 7.3 as VMWare guest losing Time - opinions
« Reply #2 on: July 11, 2008, 07:21:14 PM »
In this tread it was as far as I remember found two different ways for doing the time syncronization that both works. I don't remember the details but time syncronization has worked fine (using both methods) since then.
http://forums.contribs.org/index.php?topic=40641.0
......

Offline dvdsmith

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Re: SME 7.3 as VMWare guest losing Time - opinions
« Reply #3 on: July 11, 2008, 07:36:26 PM »
These are general problems with the 2.4.x linux kernel releases, and are oin a very low level in clock pulse frequencies set during kernel compilation. It is in the vmware documentation somewhere.

I believe bot host and guest should have the clock=pit set to have things working. More technical details are here: http://www.vmware.com/pdf/vmware_timekeeping.pdf (page 11 and 12 deal with the linux timing issues).

Thanks

Also have a look at this one: http://www.synapticsolutions.com.au/?page_id=28 , which you should have found in the forums as I have posted it multiple times (already).

I read this one.  It involves installing vmware-tools which for previous stated reasons is not an option, IMHO.  At the end it does mention setting "clock=pmtmr nosmp noapic nolapic" if clock is slow but not the custom-template fragment from mmccarn's post.

Another issue I forgot to mention is that the VMWare Server isn't mine (hosted by a friend) and I don't feel comfortable asking him to change parameters on his server to suit my needs.  He is hosting other virtual machines and I don't want to take the least chance of impacting them.  Mmccarn's solution was the only one that met the need and still allowed my server to use NTP.

Thanks for the reply

Offline mmccarn

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Re: SME 7.3 as VMWare guest losing Time - opinions
« Reply #4 on: July 18, 2008, 06:46:56 PM »
Here's a link to how I do it:
http://forums.contribs.org/index.php?topic=32139.msg139191#msg139191

I set this up when SME 7.0 was released, and it has worked ever since (almost 2 years now).

On the last virtual SME system I setup - about a month ago - I forgot all the custom template stuff and just added clock=pmtmr nosmp noapic nolapic to all of the kernel ... lines in /boot/grub/grub.conf - it seems to be working: ntpq -pn shows that I am sync'd with a time server.
« Last Edit: July 18, 2008, 07:06:37 PM by mmccarn »