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fastfwd
Contributor
Contributor

VM intermittently freezing/pausing after a datastore migration.

Hi,

I have a VM that keeps freezing at random times. Its never  under heavy load and is a decently resourced VM. After i completed a datastore migration i have these freezes. 6 other VM's are on the same datastore and host with no issues. The freezes show no error in windows or in vsphere logs.

Any ideas what it could be?

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hussainbte
Expert
Expert

there has to be some information in the vmware.log of the vm. or hostd and vmkernel logs of the host.

if you can share the three for the timestamps the issue occurs..

If you found my answers useful please consider marking them as Correct OR Helpful Regards, Hussain https://virtualcubes.wordpress.com/
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fastfwd
Contributor
Contributor

Thanks for the reply.

I went to get the hostd log and realised i didn't setup a location on the new datastore to point the host logs to. Usually vsphere would throw and error along the lines of "logs not saved on persistent storage". For some reason in this instance i didn't receive any such error so i didnt know.

Anyways i have set this up now and log files for the hosts are being collected on the new data store so i might have to wait a few days to gather some data.

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hussainbte
Expert
Expert

the vmware.log file should be available in the vm directory .. share the same if you can

If you found my answers useful please consider marking them as Correct OR Helpful Regards, Hussain https://virtualcubes.wordpress.com/
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fastfwd
Contributor
Contributor

Attached log files.

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fastfwd
Contributor
Contributor

Bump, any chance someone could help me with this issue, im a little stuck and this server continues to intermittently freeze. Log files have been attached.

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daphnissov
Immortal
Immortal

Can you upload a fresh set of logs (vmware.log [for the VM], hostd.log, vmkwarning.log and vpxa.log) and also a time when an example freeze occurred?

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DeepakNegi420
Contributor
Contributor

My findings from the log files you provided-

veem snapshot consolidation jobs is freezing the VM, refer to the following screenshot.

You are running ESXi 5.0 version and there is a hotfix available to resolve this issue-

Permanent fix-

Install hotfix VMware ESXi 5.0, Patch Release ESXi500-201408001 (2080838)

Description of the known issue-

This issue occurs if the virtual machine generates data faster than the consolidate rate

pastedImage_0.png

You can also workaround until you patch the VMhosts

  1. Shut down the virtual machine.
  2. Right-click the virtual machine and click Edit Settings.
  3. Click the Options tab.
  4. Under Advanced, click General.
  5. Click Configuration Parameters and add these parameters one at a time and check the result:

    • Set snapshot.maxIterations to 20 (or higher). The default value is 10. If you cannot converge within default maxIteration (10), you just stun and perform synchronous consolidation, which may cause the virtual machine to be stunned for a long time. If you increase maxIterations to 20 or higher, then it is possible that the virtual machine will find a period within the maxIterations to perform synchronous consolidate.

    • Change the snapshot.maxConsolidateTime to 60 seconds. The default value is 6 seconds. If you set the value to 60 seconds, the consolidate helper sees an opportunity to do the synchronous consolidate earlier (before the snapshot grows to a 30 minute issue after 10 iterations). Setting snapshot.maxConsolidateTime to 60 means that you can afford to have the virtual machine stunned for 60 seconds so the virtual machine can perform synchronous consolidate within the iterations.

      Note: There is a coefficient of 2 on maxConsolidateTime. A value of 60=120 seconds. The default is 6 but that stuns for 12 seconds.

    • Set snapshot.maxIterations to 0. Setting snapshot.maxIterations to 0 causes the virtual machine to stun and perform synchronous consolidate in the first iteration only. This may reduce the stun time.

Cheers,

Deepak Negi

  1. Shut down the virtual machine.
  2. Right-click the virtual machine and click Edit Settings.
  3. Click the Options tab.
  4. Under Advanced, click General.
  5. Click Configuration Parameters and add these parameters one at a time and check the result:

    • Set snapshot.maxIterations to 20 (or higher). The default value is 10. If you cannot converge within default maxIteration (10), you just stun and perform synchronous consolidation, which may cause the virtual machine to be stunned for a long time. If you increase maxIterations to 20 or higher, then it is possible that the virtual machine will find a period within the maxIterations to perform synchronous consolidate.

    • Change the snapshot.maxConsolidateTime to 60 seconds. The default value is 6 seconds. If you set the value to 60 seconds, the consolidate helper sees an opportunity to do the synchronous consolidate earlier (before the snapshot grows to a 30 minute issue after 10 iterations). Setting snapshot.maxConsolidateTime to 60 means that you can afford to have the virtual machine stunned for 60 seconds so the virtual machine can perform synchronous consolidate within the iterations.

      Note: There is a coefficient of 2 on maxConsolidateTime. A value of 60=120 seconds.  The default is 6 but that stuns for 12 seconds.

    • Set snapshot.maxIterations to 0. Setting snapshot.maxIterations to 0 causes the virtual machine to stun and perform synchronous consolidate in the first iteration only. This may reduce the stun time.

Vmware KB VMware Knowledge Base

Regards, Deepak Negi
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fastfwd
Contributor
Contributor

Hi Deepak,

Thankyou for your reply.

There was no such parameters as snapshot.maxConsolidateTime or snapshot.maxIterations. So i have created these parameters and set the values as you have explained. I will let you know how this goes.

Also i am unable to find vmware update manager for 5.0 under vmware downloads to install the patch. Was this named something different before, are you able to assist me in finding the installer for this so i can download it.

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fastfwd
Contributor
Contributor

Hi Deepak,

The workout around provided didnt work. Still getting the same freezing issue. Although like i said i didnt have those parameters, i thought hopefully adding them in manually would work.

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DeepakNegi420
Contributor
Contributor

VMware has also provided hotfix as a permanent fix, is it something which you can plan?
Can you send the latest logs (Vmware.log & vmkernel) files.

Regards, Deepak Negi
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fastfwd
Contributor
Contributor

I would like to complete the hotfix (patch) but as i stated in previous reply i am unable to locate the vsphere update manager. Vmware is notorious for changing their names of their products but leaving documentation with old names so anything i search for in downloads as "update manager" i am unable to find anything.

I need the update manager installed so i can complete the patch (hotfix).

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fastfwd
Contributor
Contributor

Can anyone help me with this? im still stuck on this issue.

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