CactiEZ loosing time in vmware Server on Windows 2003

[knebb]

This keeps the time darn near right on, without having to resort to running ntp once every minute or other crazy solutions,

Cool stuff. Thanks for the links, I wasn't aware there is a kernel available for CentOS. I'll see if it helps.

and without even having to install vmtools.

OT, but you should install VMware tools. It will provide you more advantages than only timesync! I.e. memory sharing and so on.

[fxef79]

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Quote:

and without even having to install vmtools.

OT, but you should install VMware tools. It will provide you more advantages than only timesync! I.e

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Agreed - I just feel like the time skew problem is something that should be solved *before* piling on additional software. That's just how I approach things - fix the problem before introducing more variables.

[eddievenus]

but for vmware tools do you not need a GUI? and does CactiEZ specifically not come with any GUI? I am not a linux guy and I have no idea how to install a gui, I tried once in cactiez0.2b but it failed and I gave up on it since the only reason I was doing it was for time sync.

As far as I can tell there are other niceties to the vmware tools if you access the server terminal often, but few other than time sync enhance a stand alone server in any way. Am I wrong? Perhaps I missed the boat here but I think this is a big deal to have to install a gui, install vmware tools and get it all running just to have good time keeping and a few memory optimizations and some cool trick where the mouse can move between host and guest seamlessly?

Seems like more work than it should be.

I will be trying the new kernel though. I just have to make sure I have the right one for CactiEZ0.3

[eddievenus]

Out of curiosity how do you replace a kernel?

I guess I will now spend some time learning another skill that I will soon never use again and forget. Oh well, c'est la vie.

EV

[cigamit]

Install the new kernel RPM, reboot and there should be a option to boot to the new kernel. Then remove the old kernel.

[eddievenus]

Jimmy,

I would like to take the opportunity to say thanks, not just for the answer to my noob question but also for the entire cactiEZ distrobution you have provided. I know that running it as a VM is not what you intended really but yet here you are helping us run your project in a way you did not design it to run. It shows strength of character to lend a hand to people who are trying to work outside of your original intended purpose for this project.

Just wanted to say thanks.

EV

[eddievenus]

fxef79 you are a genius. Your recommendation of replacing the kernel was magical. I had all the other stuff ( noapic nosmp nolapic clock=pit acpi=no) as was recommended by every site on the topic. However as you noted it made little difference.

I now have the kernel replaced with a slightly older version, but it is compiled at 100mhz. So far everthing is working, and working right as far as I can tell. I will test everything further, but unless I repost you can assume that it all works.

EV

note here is the what I did for all you other noobs (like me) who want to do this too.
1) follow fxef79's link to the centos kernel download page.
2) find a location to save it, I chose /home, so cd /home
3) download it from your CacitEZ session with wget

wget http://people.centos.org/~hughesjr/vmwa ... Z.i686.rpm

note: I am using the smp version since I have dual procs, if you do not then take the non smp kernel.
4) Install the rpm

rpm -i --force /home/kernel-smp-2.6.9-55.0.2.EL.100HZ.i686.rpm

I had to use --force since it is older than all the other kernels already included with CactiEZ.
5) finally edit /etc/grub.conf to verify it is changed, the first kernel should now show the new kernel name. Make sure it looks like this

title CentOS (2.6.9-55.0.2.EL.100HZsmp)
root (hd0,0)
kernel /vmlinuz-2.6.9-55.0.2.EL.100HZsmp ro root=LABEL=/ noapic nosmp nolapic clock=pit acpi=no
initrd /initrd-2.6.9-55.0.2.EL.100HZsmp.img

note the bold part incase you did not have that before it is the suggested fix for this problem according to VMware and most others online, it can't hurt to have.
6) Reboot

Thats it. Once it comes back up it should be happy and working.

For everyone who already knew how to do this I want you to know that there is a surprising lack of detailed information on how exactly to accomplish this online.

Many thanks to cigamit for pointing me in the right direction. Perhaps he could add this kernel as an option in future CactiEZ releases.

[fxef79]

I absolutely concur - CactiEZ has made it... well... easy to get this stuff running. Thank you, Jimmy!

eddievenus:
Anyone out there who is an *actual* linux admin, not a goofball like I am, will probably scream in pain at hearing this... I just tested the kernel-2.6.9-55.0.2.EL.100HZ.i686.rpm (found at that link I provided above) in CactiEZ 0.3 and it worked great. Technically, CactiEZ is built on a slightly newer kernel - 2.6.9-55.0.9 or *-55.0.6 I think? - so I had to force the install with:
rpm -i --force kernel-2.6.9-55.0.2.EL.100HZ.i686.rpm
(I think - that's from memory - i hope I have the switches right)

I did that on Friday to a straight up, unmodified VM install of CactiEZ 0.3. Prior to the kernel change the VM was slow by 20-25 seconds out of every "real" minute. After the kernel change, the VM was 6 seconds off on Monday after running unmolested all weekend. That's without any NTP setup and without VMtools installed. Once I install VMtools and set up NTP that's practically perfect, in my book.

I'm just testing this for a while - not live. I'll let you know if I run into any critical problems from having regressed the kernel version slightly.


[/quote]

[fxef79]

eddievenus:

Whoops! You're faster than I am! Good to see it worked on yours as well (at least I know mine wasn't a fluke!).

Frankly, eventually I plan to teach myself how to actually re-compile a kernel to do it the "right" way - but there's not enough hours in the day to do that, plus all the other stuff.

[eddievenus]

My CactiEZ0.3, with all the latest plugins (and the latest plugin arch 1.3) is now using the new 100Mhz kernel and has lost all of <1 second all day so far. I too was losing nearly 1 out of every 2 seconds. NTP was running every minute keeping me up to speed over the course of a day, but polling cycles could be 60 seconds away, 30 seconds away, or even 3 seconds away. You never know.

I could hit ntpdate us.pool.ntp.org every second and be anywhere from .001 seconds off to over a minute off. I could do the same ntpdate to my local PDC and get the same results. Now when I do that it is .0001 -.006 seconds off.

This VM is our template VM, all our production Cacti VMs are simply replicas of what I learn here. So I have to say I am very pleased to have found this information.

I am curious though, I recall seeing something about this a long time ago when I was working out time sync issues with CactiEZ0.1. I wonder what I did back then? I must have done something similar, but I am pretty sure I did not do this. Although I would not put it past me to have learned all of this once before and simply forgotten it for lack of using those skills.

[cigamit]

I will see about adding these instructions to my documentation so others can benefit from this.

[fxef79]

I built a VM from the new CactiEZ v0.4 release, and of course it's loosing time (same ratio as before - about 1:2).

FWIW, I decided to build my own kernel RPM for the 2.6.9-67.0.4 kernel used in the newest CactiEZ v0.4 build. The only thing I have done is change 1000 Hz to 100 Hz.

Frankly, I've still got some issues... I've installed the smp kernel on my VMware instance of CactiEZ v0.4 and with the grub changes mentioned before (noapic nosmp nolapic clock=pit acpi=no) I'm now GAINING a few seconds each minute. Of course, I've really confused things as this is on a completely new host server - 2x quad-core whereas my old host was a 1x P3.

I'm still going to work with the grub settings to see if I can find something that works. In the meantime, you are welcome to use the kernels I built.

However I will caution you... you are downloading the absolute first kernels I have ever successfully built... yes... "ever". Use at your own risk!!




http://www.virtualjones.com/kernel-smp- ... 686.tar.gz
http://www.virtualjones.com/kernel-2.6. ... 686.tar.gz

[fxef79]

Well, as educational as it was to finally compile my own custom kernel... it doesn't seem to have helped. I either gain or lose time depending on grub settings, but never can get it to keep right on.

In addition, I feel much safer (knowing my own linux knowledge limitations!) in moving on and using this next method...

I just used CentOS's unofficial testing repo and installed their own 2.6.9-67.0.1 kernel that has been custom compiled for VM guests.

http://wiki.centos.org/TipsAndTricks/VMWare_Server

Create the "CentOS-Testing.repo" (http://dev.centos.org/centos/4/CentOS-Testing.repo) in /etc/yum.repos.d/ and then enable it/install the VM kernel with:
yum --enablerepo=c4-testing install kernel-vm


Cheers!

[dave99]

but for vmware tools do you not need a GUI? and does CactiEZ specifically not come with any GUI? I am not a linux guy and I have no idea how to install a gui, I tried once in cactiez0.2b but it failed and I gave up on it since the only reason I was doing it was for time sync.

As far as I can tell there are other niceties to the vmware tools if you access the server terminal often, but few other than time sync enhance a stand alone server in any way. Am I wrong? Perhaps I missed the boat here but I think this is a big deal to have to install a gui, install vmware tools and get it all running just to have good time keeping and a few memory optimizations and some cool trick where the mouse can move between host and guest seamlessly?

Seems like more work than it should be.

I will be trying the new kernel though. I just have to make sure I have the right one for CactiEZ0.3

No, you do not need a gui to use vmware tools. It does help gui performance if you use one, but there are plenty of other benefits for console only operations besides the time sync (faster networking is another).

[pagemap]

Well, as educational as it was to finally compile my own custom kernel... it doesn't seem to have helped. I either gain or lose time depending on grub settings, but never can get it to keep right on.

In addition, I feel much safer (knowing my own linux knowledge limitations!) in moving on and using this next method...

I just used CentOS's unofficial testing repo and installed their own 2.6.9-67.0.1 kernel that has been custom compiled for VM guests.

http://wiki.centos.org/TipsAndTricks/VMWare_Server

Create the "CentOS-Testing.repo" (http://dev.centos.org/centos/4/CentOS-Testing.repo) in /etc/yum.repos.d/ and then enable it/install the VM kernel with:
yum --enablerepo=c4-testing install kernel-vm


Cheers!

How do you create it though? Can you tell me the commands to get the CentOS-Testing.repo onto my VM, so that I can then install it. Thanks!