Solution to Host not responding in SC VMM

Posted on January 6, 2016 by Rajeev

I have been troubleshooting a WinRM related problem which was the main cause of an error shown in SC Virtual Machine Manager as “Host not responding”. The error always pointed to Win RM or Windows Management. I tried a lot of fixes, but nothing worked. Eventually I thought to rebuild the Windows Management repository. Here are the steps I took to fix this issue:

Run this command on the errant server: net stop winmgmt (You will have to do this multiple times, or the step #2 will give you an error, file in use)
rename the folder ‘Repository’ underneath %windir%\system32\wbem
restart the system
Done

The repository will be rebuilt automatically, OR you can rebuild it manually by running this command winmgmt /resetrepository (I did not have to do this)

PS: This also fixes the error in Server Manager which shows up under NIC teaming – “Host Unmanagable”

Avocent UMG 4000 problems

Posted on July 24, 2015 by Rajeev

ok so we we just bought a new KVM, a Avocent UMG 4000. I am very unhappy to report that we have multiple problems with this device.

I have opened multiple tickets to get these issues resolved with Avocent’s tech support. The good thing is that the tech support is responsive and helpful. However, I feel that these are basic things which should work right out of the box for any KVM. The old Avocents we had worked fine, for over a decade! These basic KVM features work fine even in $50 KVM switches. This UMG 4000 is a $10,000 dollar product!

Needless to say, I am VERY disappointed with our purchase of UMG 4000!

The tech support says that most of these issues will be addressed via firmware updates. I will post a review of our Avocent UMG 4000 as and when that happens.

For now, here are some of the issues:

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Fix “missing” VM status in VMM

Posted on July 20, 2015 by Rajeev

OK so here is a tricky problem with an easy fix.

Sometimes, in SC VMM 2012 some of my VMs are shown as “missing”. I cannot do anything to them using VMM. An easy fix is to fire up FCM (Failover Cluster Manager) and live migrate or quick migrate the VM (depending upon whether the VM is running or not). After that VMM will immediately refresh the VMs state to the correct one….stopped or running.

Problem:

Solution:

VM Additions not detected?

Posted on January 15, 2015 by Rajeev

From time to time, I run into this issue with our Hyper-V environment. No matter how many times I upgrade the VM additions, SCVMM still is not able to detect it. It always ends up saying “not detected”.

Eventually I noticed that one of the the 6 Hyper-V related services which are usually running on the VM was having some trouble – the heartbeat service. Hmmm…that makes sense!

If I tried to start this service, I got the following error:

Error 1083: The executable program that this service is configured to run in does not implement the service.

While doing some searching on the net, I found out the solution here !!THANK YOU!!

As mentioned by that guy, the two things I need to know are shown below:

So I open the registry and add vmicheartbeat to the bottom of this Multi-String entry, like this:

After I click OK and restart the VM, the heartbeat service starts without any problem (automatically). Just do a refresh in VMM and now I see the VM additions version number. Yeah baby!

Thanks a lot to Jeremy!

What is Driver Locked memory?

Posted on November 11, 2014 by Rajeev

I noticed that one of my VMs (on Hyper-V 2012) was using a lot of RAM. Strangely, there was no application which was using that much RAM. It was using 14.2/16 GB RAM. At that time task manager showed this:

And this in the details tab:

Notice that Oracle was using only 1.8GB and that was the highest user. Even if I total everything, it still was nowhere near 14 GB used. What was using all that RAM?