Skip to main content

Issue: Operating System not found


                   

Yesterday, I was working into my vsphere Lab where I have deployed one virtual machine into the environment. After deployment virtual machine was working perfectly fine. After some time, I have added 2 huge hdd of size 800 GB using PVSCSI. Once I added the hdd into the VM, and after accepting the change, I tried to open the console and found vm has rebooted and stuck at "Operating System not found"





That’s look wired, as I have just added the hdd online and suddenly it rebooted and stuck at this stage.
To troubleshoot this issue I tried to gracefully shutdown the VM and tried to bring online in hope, it will detect the changes, but again it stuck at same level "Operating System not found"

I checked my OS drive which is created with the LSI SCSI controller, and the 2 new hdd I created with PVSCSI controller. Here is what the problem exists!!!!!
Basically, When the virtual machine is created with the LSI SCSI controller, the operating system controller is selected as the first boot controller. Now when the controller type is changed to PVSCSI, it is detected as a new device and the controller with the data drive may be moved to the first boot controller. When it fails to find the operating system during bootup, this issue occurs.
Now the issue has been isolated as why the virtual machine is not booting with OS.
I planned to set the "scsi0;0" with the first boot controller.
To do so I perform below steps,

This is applicable from Esxi5.0 or later.

  1. Power off the virtual machine.
  2. Login to the Esxi using Putty or using Tech Support Mode
  3. Access the VMFS volume where the virtual machine is located using below command

    cd /vmfs/volumes/datastore_name/vm_name  
  4. Once VM folder is identified, open the its vmx file in vi (text editor)
  5. Make sure the VM is in powered of state
  6. Add this line to the .vmx file:

    bios.hddOrder = "scsi0:0"
  7. Save the changes into .vmx file.

  8. Now we need to reload the  .vmx file. to recognize the changes.
 To reload the .vmx file please use below steps:
    1. Fist we have to obtain the Vmid of the virtual machine using below command:
    2. #vim-cmd vmsvc/getallvms
    3. You see output similar to: 
      Vmid Name File Guest OS Version Annotation 2848 Win2003_storage_performance [local] Win .vmx winNetEnterpriseGuest vmx-07 To be used as a template
    4. In this example, the Vmid is 2848.
    5. Reload the .vmx file using this command:

      # vim-cmd vmsvc/reload Vmid
  1. Now Poweron the VM, Your VM wil boot now with OS  :)

Happy Sharing.

Comments

Popular posts from this blog

Changing the FQDN of the vCenter appliance (VCSA)

This article states how to change the system name or the FQDN of the vCenter appliance 6.x You may not find any way to change the FQDN from the vCenter GUI either from VAMI page of from webclient as the option to change the hostname always be greyed out. Now the option left is from the command line of VCSA appliance. Below steps will make it possible to change the FQDN of the VCSA from the command line. Access the VCSA from console or from Putty session. Login with root permission Use above command in the command prompt of VCSA : /opt/vmware/share/vami/vami_config_net Opt for option 3 (Hostname) Change the hostname to new name Reboot the VCSA appliance.   After reboot you will be successfully manage to change the FQDN of the VCSA . Note: Above step is unsupported by VMware and may impact your SSL certificate and face problem while logging to vSphere Web Client. If you are using self-signed certificate, you can regenerate the certificate with the

Collecting Logs from NSX-T Edge nodes using CLI

  This article explains how to extract the logs from NSX-T Edge nodes from CLI. Let's view the steps involved: 1) Login to NSX-T  Edge node using CLI from admin credentials. 2) Use of  " get support-bundle " for Log extraction. get support-bundle command will extract the complete logs from NSX-T manager/Edge nodes. nsx-manager-1> get support-bundle file support-bundle.tgz 3) Last step is to us e of " copy file support-bundle.tgz url " command. copy file will forward your collected logs from the NSX-T manager to the destination(URL) host from where you can download the logs. copy file support.bundle.tgz url scp://root@192.168.11.15/tmp Here, the URL specified is the ESXi host ( 192.168.11.15) under /tmp partition where logs will be copied and from there one can extract it for further log review. Happy Learning.  :)

Removing NSX-T manager extension from vCenter

In NSX-T starting from ver 2.4 NSX-T appliance got decoupled from vCenter where now its not mandatory to run NSX-T on vCenter platform only. Now NSX-T can be managed through standalone ESXi host, KVM or through container platform. As in version 2.4 there is still an option available to connect vCenter to NSX-T using Compute Manager. Here in this blog we will learn how we can unregister and register NSX-T extenstion from vCenter in case of any sync or vCenter connectivity issue with NSX-T. Lets get started.. 1) Login to NSX-T UI Go to -> System ->Compute Manager Here, vCenter is showing in Down status where the status is showing as "Not Registered" 2) When we click on "Not Registered" option its states below error. 3) When try to click on Resolve option its states below. At this stage if the Resolve option doesn't work then its require the remove the NSX-T extenstion from vCenter. To remove the NSX-T e