HOW TO:  Resize a VMware (VMDK) Virtual Disk

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Andrew Hancock (VMware vExpert / EE MVE^2)
MVE^2, Expert of the Year 2017-2011, Scribe 2016-2012, Author of the Year 2017-6,2013-2012 VMware vExpert 2018-2011 27 years of experience.
HOW TO:  Resize a VMware (VMDK) Virtual Disk

To re-size a disk, select the Virtual Machine, select Edit Settings, highlight the Virtual Hard Disk, and select Edit - there is an option to increase size. This only changes the physical size of the virtual disk, it does not grow the partition on the disk. If this option is unavailable and grayed out, you may have an IDE disk, which does not support expansion, or you may have a snapshot atttached to the virtual disk.

Always ensure you have a full backup  - not a snapshot -  before any disk expansion or partition alterations.

1. Resize partition with Gparted Live CDROM

Using GParted Live CDROM to extend a partition
i. Download Gparted Live CDROM from here

ii. Upload the cdrom iso to the vSphere ESX/ESXi datastore.

iii. Mount the cdrom or iso on the virtual machine.

iv. Shutdown and restart the virtual machine booting from the cdrom.

v. Select Resize partition.

Here is a Tutorial Walkthorugh of how to resize a partition with a GParted Live CDROM


2. Using DISKPART.exe

Using Diskpart to Extend a Partition
(the system disk cannot be re-sized within the virtual machine, but other disks can be resized, eg. D: E: etc)

i. Shutdown the virtual machine.

ii. Remove disks from virtual machine (but do not delete them).

iii. Add the disks to another virtual machine.

iv. Start up virtual machine.

v. Use Diskpart in the OS to extend disks.

see here for details on Diskpart usage

3. V2V using VMware vCenter Converter Standalone.

Using VMware vCenter Converter Standalone to create a V2V
Using  VMware vCenter Converter Standalone, create a new virtual machine, e.g. V2V, and specify new virtual disk size. This will increase the size of the virtual disk and partition in one process.

I would recommend and use VMware vCenter Converter Standalone 5.0

and if you do use VMware vCenter Converter Standalone 5.0, and you want to make your transfers 60% faster checkout my EE article here

HOW TO: Improve the transfer rate of a Physical to Virtual (P2V), Virtual to Virtual Conversion (V2V) using VMware vCenter Converter Standalone 5.0

Download VMware vCenter Converter 5.0 here
VMware vCenter Converter Standalone 5.0 Documentation
VMware vCenter Converter Standalone 5.0 User Guide

If you have issues, you may want to consult the following articles and guides

Read fellow Expert Bestway's article.

Best Practice Video Guide here

Some videos I've develeoped for Experts Exchange members showing VMware vCenter Converter Standalone in use

A Tutorial video by me:- Restore a Virtual Machine using the FREE VMware vCenter Converter to VMware vSphere 4.x, 5.0 ESXi 4.x, ESXi 5.0, ESX 4.0

A Tutorial video by me:- Backup VMware vSphere 4.x, 5.0 ESXi 4.x, ESXi 5.0, ESX 4.0 for FREE using VMware vCenter Converter

A Tutorial video by me:- VMware vCenter Converter Standalone Process at work

A Tutorial video by me:- VMware vCenter Converter Standalone 5.0 Convert monolithic sparse to monolithic flat for use with VMware vSphere 4.x 5.0 ESXi 4.x 5.0

4. Using Dell Extpart.exe

Using Dell ExtPart to extend a partition
Download Dell Extpart.exe from here

The Dell Extpart utility will expand boot drives on WindowsXP/2000/2003 without downtime.  Dell Extpart is not compatible with 64 bit operating systems, so I would suggest an alternative option Windows 2008 R2 and Windows 7, the Extend partition option in Disk Management can be used, otherwise use an alternate method listed in this article.

5. Windows 2008, Windows 2008 R2, Windows 7 and later

Using Disk Management to Extend a Partition
Using Disk Management, you can select the partition, right click and select Extend.

These are just a few free options to extend a partition in a virtual or physical machine. Many other third party applications exist to extend a partition.

Examples of third-party utilities I've also tested and use to increase partitions:

7tools Partition Manager


EASEUS Partition Manager

Partition Logic      

Paragon Partition Manager      

Ranish Partition Manager

System Rescue CD

Again, please ensure you have a valid backup before attempting any virtual disk or partition changes. This does not include a snapshot. A snapshot is not a backup.

Thank you for reading my article, please leave valuable feedback. If you liked my VMware article and would like to see more VMware Articles from me, please click the Yes button near the: Was this article helpful? at the Bottom of this article to the right. Thank You.
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Expert Comment

Another excellent resource for all members here on EE.

"Yes" vote above.

Expert Comment

Dell Extpart will run on 64-bit 2k3, extract the exe via winzip or 7-zip as it is only an archive that performs the arch check.  Once extracted, extpart should work fine.
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Author Comment

by:Andrew Hancock (VMware vExpert / EE MVE^2)
Caused crashes on 64bit Windows 7 and Windows 2008 R2 hence, why I recommended a different utility, especioally when completing disk expansion, the last thin you want is corrupted partition because the utility crashed.

Up to the EE Reader to experiment, and use whatever they are happiest with, they should always have a backup before any disk expansion! But thanks for your response.

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