From VMware KB-2045616
Symptoms
- Unable to power on a virtual machine with a mounted sparse disks.
- You see the error:
An error was received from the ESX host while powering on <vm_name>. Cannot open the disk '/vmfs/volumes/datastore_path/vm_folder/vm_name-000001.vmdk' or one of the snapshot disks it depends on. The system cannot find the file specified VMware ESX cannot find the virtual disk "/vmfs/volumes/datastore_path/vm_folder/vm_name-000001.vmdk". Verify the path is valid and try again.
- In the vmware.log file on the virtual machine, you see entries similar to:
Failed to open '/vmfs/volumes/datastore_path/vm_folder/vm_name-000001.vmdk' with flags 0xa The system cannot find the file specified (25). Worker#1| I120: Msg_Post: Error Worker#1| I120: [msg.disk.fileNotFound] VMware ESX cannot find the virtual disk "/vmfs/volumes/datastore_path/vm_folder/vm_name-000001.vmdk". Verify the path is valid and try again. Worker#1| I120: [msg.disklib.FILENOTFOUND] The system cannot find the file specified Worker#1| I120: [msg.disk.noBackEnd] Cannot open the disk '/vmfs/volumes/datastore_path/vm_folder/vm_name-000001.vmdk' or one of the snapshot disks it depends on.
Note: This article applies to twoGbMaxExtentSparse disks as created and used on ESX/ESXi 4.x and earlier hosts. Such disks are disallowed on all ESXi 5.x hosts.
Cause
This issue occurs because sparse disks are not a compatible disk format on ESXi hosts.
Resolution
To resolve this issue, convert the sparse disks to a supported format with vmkfstools and then add them to the virtual machine.
To convert sparse disks to a supported format:
- Log in to the ESXi/ESX host as the root user.For more information, see Using ESXi Shell in ESXi 5.0 and 5.1 (2004746) or Using Tech Support Mode in ESXi 4.1 and ESXi 5.x (1017910).
- Navigate to the virtual machine folder by running this command:
cd /vmfs/volumes/datastore_name/ vm_name
- To verify if the virtual machine is associated with sparse disk(s), view the contents of the .vmdk file, run this command:
cat vm_name.vmdk
You see the output similar to:
Disk DescriptorFile version=1 CID=56ed7313 parentCID=ffffffff isNativeSnapshot="no" createType="twoGbMaxExtentSparse"
Extent description RW 4192256 SPARSE "xxxxxxxxx-s001.vmdk" RW 4192256 SPARSE "xxxxxxxxx-s002.vmdk"
Note: twoGbMaxExtentSparse refers to a sparse disk with a maximum 2 GB extent size.
- Clone all the sparse disks to a compatible format with vmkfstools by running this command:vmkfstools -i source_file destination_file -d thin
Note: Replace thin with thick as required. For more information, see Cloning and converting virtual machine disks with vmkfstools (1028042).
- When the clone process completes, remove the sparse hard disk(s) associated with the virtual machine.
- Add the new cloned virtual hard disks.Note: In vSphere Client, right-click the virtual machine and click Edit settings. Navigate to Hardware tab > Add > Hard Disk. Select Use an existing virtual disk. Browse to locate the new hard disk file and complete the wizard.