Converting a virtual IDE disk to a virtual SCSI disk (1016192)

Symptoms

  • Virtual machine contains an IDE virtual disk as the primary OS bootable disk after conversion from physical source.
  • Virtual machine has an IDE virtual disk but the additional secondary virtual disks are SCSI with an LSI or Bus Logic controller.
  • Virtual machine fails to boot with only a black screen after conversion with possible underscore. The Primary disk is an IDE virtual disk but LSI or Bus Logic was selected during conversion.
  • After conversion using P2V, the virtual machine fails to boot.
  • Virtual machine created after P2V failed between 95% and 99% and fails to boot.
  • After powering off a virtual machine, you are unable to increase the size of its hard disk(s) when the disk is not SCSI based.

 

Resolution

When converting a physical machine to a virtual machine using VMware Converter or vCenter Converter Enterprise, if an adapter type is not selected during the initial customization the resulting virtual machine may contain an IDE disk as the primary OS disk.

You must convert the IDE disk to SCSI to get the best performance. If the primary disk is an IDE virtual disk, the newly converted virtual machine may fail to boot because the guest OS does not support the driver. Second reason for this issue is that in ESX 4.x the default disk type for Windows XP 32bit virtual machine creation is IDE. This default value can be manually changed during the virtual machine creation wizard by selecting the custom option. Windows XP 64bit will still use SCSI by default.

Note: For newer versions of Windows and Linux OS guests, the typical SCSI adapter types are the LSI Logic controllers. When using LSI Logic SCSI controllers in the Windows XP virtual machine, ensure to download and install the appropriate LSI driver before proceeding. For more information on downloading and installing LSI Logic SCSI drivers, see Storage Drivers for ESX 3.5.x and Microsoft Windows XP When Using the VMware LSI Logic Storage Adapter (1007035).

In situations where you are manually changing an IDE disk to a SCSI disk that holds a Windows Operating system volume, you may need to repair the master boot record of the disk. Please see  Repairing boot sector problems in Windows NT-based operating systems (1006556)

To convert the IDE disk to SCSI:
  1. Locate the datastore path where the virtual machine resides.

    For example:

    # cd /vmfs/volumes/<datastore_name>/<vm_name>/
  2. From the ESX Service Console, open the primary disk (.vmdk) using the vi editor. For more information, see  Editing files on an ESX host using vi or nano (1020302)
  3. Look for the line:

    ddb.adapterType = "ide"
  4. To change the adapter type to LSI Logic change the line to:

    ddb.adapterType = "lsilogic"

    To change the adapter type to Bus Logic change the line to:

    ddb.adapterType = "buslogic"
  5. Save the file.
  6. From VMware Infrastructure/vSphere Client:
    1. Click Edit Settings for the virtual machine.
    2. Select the IDE virtual disk.
    3. Choose to Remove the Disk from the virtual machine.
    4. Click OK.

      Caution: Make sure that you do not choose delete from disk.

  7. From the Edit Settings menu for this virtual machine:
    1. Click Add > Hard Disk > Use Existing Virtual Disk.
    2. Navigate to the location of the disk and select to add it into the virtual machine.
    3. Choose the same controller as in Step 3 as the adapter type. The SCSI ID should read SCSI 0:0.

  8. If a CDROM device exists in the virtual machine it may need to have the IDE channel adjusted from IDE 0:1 to IDE 0:0. If this option is greyed out, remove the CD-ROM from the virtual machine and add it back. This sets it to IDE 0:0.

Additional Information

In some cases, a primary operating system virtual disk is set up as IDE while the additional virtual disks are set up as LSI or Bus Logic SCSI disks. In this situation, after editing the IDE disk adapter type and removing the disk from the virtual machine in Edit Settings, you must change the SCSI channel for the secondary disks to free up SCSI 0:0 for the main OS disk.
 
Change the SCSI 0:0 disk to SCSI 0:1, then when you add the primary OS disk back into the virtual machine with the new LSI Logic adapter type, you can select SCSI 0:0 for the disk.
 
Target virtual machines that were converted to ESX 4.0 or ESXi 4.0 hosts using volume-based cloning fail to start up if they contain IDE disks. For more information, see the VMware vCenter Converter Standalone 4.0.1 Release Notes.

See Also

Update History

10/28/2011 - removed edit from step 2 in resolution. Made no sense to have open edit. 06/27/2012 - Added link to using the vi editor.