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Increasing the size of a virtual disk


This article guides you through the process of increasing the size of a virtual disk. This procedure is necessary to accommodate data requirements that have changed since the creation of the virtual disk.


Important information before you begin

Even though this article provides steps to increase the size of your virtual disk, the size of the disk partition does not increase as observed inside the guest operating system. You must follow steps related to your specific operating system to increase the size of the disk partition(s). For more information, see Increasing the size of a disk partition (1004071).
Caution: VMware recommends that you back up your virtual machine before increasing the size of virtual disks.
The procedure for increasing the size of a virtual disk differs between VMware products. Follow the section below that matches your product.
In all cases, confirm the following before increasing the size of the virtual disk:
  • All snapshots have been removed. For additional information, see Working with snapshots (1009402).
  • The virtual machine is powered off.

Instructional Notes

To follow the sections below, replace any reference to vm.vmdk with the full path to the virtual machine's virtual disk.

Note: If you have multiple .vmdk files with the same base name, use the file that does not include -flat or -s0 in its file name.

You may need to:

  • Locate the full path to a hosted (non-ESX host) virtual machine's virtual disk (.vmdk ) file. For more information, seeLocating a hosted virtual machine's files (1003880).
  • Locate the full path to an ESX host's virtual machine's virtual disk (.vmdk ) files. For more information, see Verifying that ESX virtual machine storage is accessible (1003751).

Workstation / Player 3.x / ACE Manager / Server / GSX

To increase the virtual disk from the command line:

  1. Open a command prompt. For more information, see Opening a command or shell prompt (1003892).
  2. Navigate to the product's installation directory. For more information, see Locating a VMware product's installation directory (1003897).
  3. Type vmware-vdiskmanager -x 100Gb vm.vmdk and press Enter.

    Note: Replace 100Gb with the actual size of virtual disk that you want. You can also specify Kb and Mb.
  4. Follow the steps in Increasing the size of a disk partition (1004071) so the guest operating system is aware of the change in disk size.
For Workstation 7 and later and Player 3.x and later, you can increase the virtual disk from the GUI:
  1. Select the virtual machine from the Inventory.
  2. Click Edit Virtual Machine Settings.
  3. Click Hard Disk.
  4. Click Utilities > Expand, enter the new size, then click Expand.
  5. Follow the steps in Increasing the size of a disk partition (1004071) so the guest operating system is aware of the change in disk size.

VMware Player 2.x / ACE Instance

It is not possible to directly change the size of a virtual machine's virtual disk if VMware Player 2.x is being used or if it is an ACE Instance.
  • If you are using an ACE Instance, the virtual disk size must be changed from the ACE Manager, then repackaged and redeployed.
  • If you are using VMware Player's 2.x, upgrade to VMware Player 3. This is a free download, available from ourDownload Center.

ESX / VI Client / vSphere

  • In ESX 4.1, you can extend and add virtual disks to a virtual machine when it is powered on (after installing VMware Tools).
  • Ensure the user has sufficient permissions to carry out this task.

This error may occur because of a number of different issues:
Failed to open the disk 'vm.vmdk' : A file was not found (0x1900000004)
If you experience this error, ensure that you can power on the virtual machine successfully and ensure that you remove all snapshots. For additional information, see Determining if a virtual machine is using snapshots (1004343). If the error persists, contact VMware Support.
If you have ESX 3.5 or newer:
  1. Open VMware Infrastructure (VI) Client and connect to VirtualCenter or the ESX host.
  2. Right-click the virtual machine.
  3. Click Edit Settings.
  4. Select Virtual Disk.
  5. Increase the size of the disk.

    Note: If this option is greyed out then the disk may be running on snapshots or the disk may be at the maximum allowed size depending on the block size of the datastore
  6. Follow the steps in Increasing the size of a disk partition (1004071) so the guest operating system is aware of the change in disk size.

For earlier versions of ESX, you must use the Console. For more information, see Adding Space to an ESX Server Virtual Disk (994).

For further details on Virtual Disk Configuration, you can reference the vSphere Virtual Machine Administration Guide.

Lab Manager

Warning: Any attempt to resize a configuration's virtual disk in Lab Manager results in total data loss. Do not attempt to resize the virtual disk. Create a new virtual machine with a virtual disk of the size desired. When you have completed creating a new virtual machine, create a backup of the virtual machine from within the guest and then restore the backup to the newly created virtual machine.
Note: The following procedure applies to templates only.  Do not attempt to resize a configuration.
  1. Open Lab Manager.
  2. Consolidate and then deploy the template to be resized. For instructions, see the Lab Manager User's Guide.
  3. Connect to the ESX host where the template was deployed using VI Client.
  4. Perform the disk resize according to the ESX section above. 
  5. Follow the steps in Increasing the size of a disk partition (1004071) so the guest operating system is aware of the change in disk size.

    Original KB link: 1004047

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