Cannot attach a disk backed up by VMware Consolidated Backup to a virtual machine hosted on ESX
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Cannot attach a disk backed up by VMware Consolidated Backup to a virtual machine hosted on ESX


Article ID: 306690


Updated On:


VMware vSphere ESXi


  • You cannot directly attach a disk backed up by VMware Consolidated Backup to a virtual machine hosted on ESX.
  • If you try to attach a disk, you see the error:

    Failed to open disk scsi0:3 : Unsupported and/or invalid disk type


VMware ESXi 3.5.x Installable
VMware ESXi 3.5.x Embedded
VMware ESX 4.0.x
VMware ESX 4.1.x
VMware ESX Server 3.5.x
VMware ESXi 4.1.x Embedded
VMware ESX Server 3.0.x
VMware ESXi 4.1.x Installable
VMware ESXi 4.0.x Installable
VMware ESXi 4.0.x Embedded


The VMware Infrastructure (VI) Client and VMware vSphere Client generate a 2gbsparse disk by default when creating a template, or when backing up a virtual machine using VMware Consolidated Backup.

However, the 2gbsparse disk cannot be used with virtual machines hosted by ESX. The disk must be converted to a supported format.

Converting virtual machine disks to a supported disk type

Note: Before performing these steps, ensure that the disk you want to access is stored on a location accessible to the ESX host (for example, on a LUN, local disk, or NFS datastore).
  1. Log in to the VMware ESX host as root using an SSH client.
  2. Change to the directory containing the disk using cd.
  3. Run the following command to list the contents of the directory:

    ls -l disk*

    A portion of the output includes lines similar to:

    -rw------- 1 root root 327680 May 28 15:04 disk-s001.vmdk
    -rw------- 1 root root 196608 May 28 15:04 disk-s002.vmdk
    -rw------- 1 root root 359 May 28 15:04 disk.vmdk

  4. Run the following command to clone the disk to a datastore:

    vmkfstools -i disk.vmdk -d <diskformat> /vmfs/volumes/<datastore>/newdisk.vmdk

    Where /vmfs/volumes/<datastore>/newdisk.vmdk is the destination location and name for your virtual disk clone.

    Note: The disk format can be thin, zeroedthick, or eagerzeroedthick. For more information about these formats, see the Additional Information section in Cannot power on a virtual machine because the virtual disk cannot be opened (1004232).

  5. Run the following command:

    ls -l /vmfs/volumes/<datastore>/ls -l disk*

    The output appears similar to:

    -rw------- 1 root root 3221225472 May 28 15:05 disk-flat.vmdk
    -rw------- 1 root root 307 May 28 15:05 disk.vmdk

  6. Connect to the ESX host with VI Client or to the vSphere Client directly or though vCenter.
  7. Select the virtual machine on the ESX host.
  8. Depends of the guest operating system capabilities, edit the virtual machine's properties to either hot add or cold add the disk.
  9. When the disk attached to the virtual machine, consult the guest operating system documentation for instructions on how to access the data on the newly attached disk.

Additional Information

For more information about supported disk formats, see the manual pages for vmkfstools:

man vmkfstools

Where the manual pages are unavailable, such as on VMware ESXi, run vmkfstools without additional arguments:


VMware Consolidated Backup でバックアップしたディスクを ESX にホストされた仮想マシンに接続できない