vSphere Hypervisor

I am runnung vsphere ESXi 4.1

I was recently told by a coworker that I could increse the number of vCPUs on my virtual machines to make them a bit faster.  I decided to try this on my OS deployment server to see if it would indeed increase my speed.  I followed the directions in the vSphere manual, for increasing the CPU number.  Once done, I started the VM and now it will not boot.  It just stays on the black screen and says "Operating System not found".  I have checked the boot order and that is right.  I also put in the install disk to try and do a boot sector fix, but the installation couldn't find the installed OS either.  ARGH!!!  Any help would be marvelous!

The other 2 VMs are running fine.

Thanks,

Tim

Welcome to the Community - What is the operating system of the VM? Is it the OS configured to support SMP and the number of vCPUs you have assigned to the VM? Some operating require changes in the kernel/HAL to support multtiple CPUs

I was recently told by a coworker that I could increse the number of vCPUs on my virtual machines to make them a bit faster

Please don't take this as a general rule of thumb. Increasing the vCPU count for the VMs can improve or degrade overall performance. Keep in mind that the ESXi host shares the physical resources between the VMs. It depends on the number of physical CPUs/cores, the number of VMs, the workload, ... whether increasing the vCPU count leads to better performance. You may certainly try this, but please keep an eye on the overall performance for all VM's running on the host.

Regarding your initial question, please provide the information weinstein5 asked for as well as some details about the physical hardware.

André

Thanks for the speedy replies.  Here is a bit more information on the hardware and OS.  This VM was configured with 1 CPU, I was just trying to increase it to 2.  It is running Windows Server 2008 R2 x64.  Everything I read said this should have worked.  I followed these instructions while increasing the CPU setting:

I also added the "cpuid.coresPerSocket" setting to the Configuration Parameters which I was told to do in another manual.  Everything I read says that this should have worked just fine.  Now I just get "Operating System not found"  when I boot it up...

Here is the specs of the ESXi host:  2 x 6core Xeon Processors, 32 GB RAM.  There are 2 other virtual servers on this machine, both only using 1 processor each.  I have plenty of resources available for use.

I would really just like to get this VM back up and running,  I really don't care if it only has 1 CPU or 2, I just want it to work.  Any ideas?

-Tim

Since the "Operating System not found" message seems to come from the OS installation, you could try to boot the VM from the Windows 2008 R2 DVD (or ISO) into repair mode and let the wizard fix the boot config. Before you try anything, make sure you take a snapshot of the VM to be able to at least revert to the current state.

André

sorry to ask you but do you have FT configured? vmware 4.x support 1 vcpu only for FT I suppose.

Timmynimmy84 wrote:

I would really just like to get this VM back up and running,  I really don't care if it only has 1 CPU or 2, I just want it to work.  Any ideas?

have you simply tried putting the VM back to the settings they were originally?!?  If the CPU usage for a VM isn't high (performance monitor will show this in history) then obviously the CPU is NOT the issue....

RParker  yes made look to performace monitor.

Cheers,

Denis

I do not have FT enabled.

I have also tried just putting the settings back to the way they were... no luck...

I have also tried booting from the install DVD but it doesn't recognize the OS install and says I need to install drivers to read the drives.  Even though the drives from that machine are accessable without loading drivers...

I do have a snapshot that I can restore to, however it was taken a while ago and many changes have been made since then.  I was just hoping someone might have a fix so I don't have to start from that snapshot...

Update-

I have sucessfully booted this VM with the help of Hirens boot disk!  One of the options is to run BOOTMGR and this worked to boot the server.  It seems to run fine once it's booted however the moment I reboot it goes back to Operating System not found.  I tried to run the recovery cd but when it comes to the page where you select an OS to repair, the list is blank.  It claims that I need to load drivers however when I click to load the drivers the drives from that server are visible and accessable!  WEIRD.  So I guess I am in need of some assistance to recover/rebuild the BOOTMGR for this server.  Any thoughts?

Thanks,

Tim

You should be able to click the "Next >" button without loading drivers and then select the "Startup Repair" tool.

André

PS: Again, make sure you take a snapshot before doing this (unless already done).

when I click next I only get 3 options:

Windows Complete PC Restore

Windows Memory Diagnostic Tool

Command Prompt

I selected command prompt and ran StartRep.exe

It ran through a repair and said it applied fixes.  I rebooted and still got the Operating sustem not found.

A little more info:

it always tries to do a network boot if there isn't a boot CD in the drive.  I have changed the boot order in the bios and selected Hard Drive from the boot list (after hitting Esc durring the VMware splash screen) to no avail.  It just keeps trying to do a network boot.

I did take a snapshot so I am covered there.

Can you please attach the latest vmware.log from the VM's folder to your next post!?

You could also try to set the boot partition "Active" using diskpart from either the "Repair Mode" command prompt or once booted using the boot CD. If you are not familiar with diskpart, let me know and I will provide the steps.

André

I did set the partition to Active while I was booted last, no luck.  I have attached the most recent log.

Thanks!

You disks are connected in an unusual way. Usually scsi0:0 is the first disk, which would mean "Groves2008-2-000006.vmdk" in your case. Can you confirm the shown setup is correct?

What's the output of "detail disk" for each of the 3 disks in diskpart?

from the log file:

Dec 14 20:44:10.688: vmx| DICT          scsi0:6.fileName = Groves2008-2-000006.vmdk
Dec 14 20:44:10.688: vmx| DICT          scsi0:8.fileName = Groves2008-2_1-000004.vmdk
Dec 14 20:44:10.688: vmx| DICT          scsi0:0.fileName = Groves2008-2_2-000001.vmdk

André

that is the way it is setup... I'm not sure why... Can this be changed?

As mentioned, it is unusual. That does not mean it's incorrect. Maybe the diskpart output will help. Since there are also a couple of snapshots on the disks the .vmsd file might include some hints too.

André

I am the one who set it up and I have no idea why I did it this way.  So it probably is wrong.  I have attached the disk details for each disk as well as the .vmsd file you requested.

According to the vmsd file it looks like the SCSI-ID's of your disks got exchanged (for whatever reason, please don't ask me)

I fixed the .vmx file so the .vmdk disks will be presented to the VM using the original SCSI-ID's.

scsi0:0.fileName = "Groves2008-2-000006.vmdk"
scsi0:1.fileName = "Groves2008-2_1-000004.vmdk"
scsi0:2.fileName = "Groves2008-2_2-000001.vmdk"

Please make sure you did not take another snapshot and these are the latest .vmdk files!

To replace the .vmx file, first remove the VM from the inventory (right click the VM in the Inventory -> "Remove from Inventory"), then upload the attached .vmx file to the VM's folder on the datastore and lastly right click the .vmx file and select "Add to Inventory".

Before powering on the VM, take another snapshot to make sure you we have a way back if this does not turn out as expected!

If it works you should consider to "Delete All" snapshots from the Snapshot Manager.

André

Thank you sooo much for your help!!!

I followed your directions and now it is not trying to do a network boot anymore!!  However, it is now coming up and saying "BOOTMGR is Missing".  I tried using the Windows CD but it still wont find my windows install to do a startup repair.  I tried downloading the recommended drivers and it says they are not correct...

Edit:

Nevermind!! I had taken a new snapshot so I just changed the vmx file to match the newer vmdk file names  and it worked!!!

Thank you soooooo much for your help!!!!!