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Can I increase  the size of the harddisk of a Virtual machine running on ESX host vmware 4.0


I have machine with 40GB of the c drive, is there a way to extend the size of the hard disk of the VM. I am looking for the option to increase the size of the c drive on the hard disk.

Did shutdown the virtual machine and from edit settings have increased the provisioned size of the hard disk but it reated a seperate partition on the VM. Is there a way to extend the existing drive in a VM.

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How to Resize a Partition after Disk Expansion

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. See below.

Before making any changes to the partition structure of the disk, ensure you have a full backup, not a snapshot.

1. Resize partition with Gparted Live CDROM

i. Download Gparted Live CDROM (http://gparted.sourceforge.net/livecd.php).

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

(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.Use VMware Converter Standalone to complete a V2V (virtual to virtual conversion).
there is an option to increase or decrease the size of target disks on the desintation at conversion.

Download VMware vCenter Converter here


VMware vCenter Converter Standalone 4.x Documentation


VMware vCenter Converter Standalone 4.3 User Guide


For the conversion steps, read fellow Expert Bestway's article.


Best Practice Video Guide here


Also the VMware KB here

Danny McDanielClinical Systems Analyst

if it's windows, you can shutdown the VM, attach the disk to a helper VM that's running windows, open command prompt and run diskpart, 'list volume' then 'select volume #' for the correct one, then enter 'extend'.  that should extend the partition, exit diskpart, remove the disk from the helper vm and bootup the vm you just extended.
Paul SolovyovskySenior IT Advisor
Top Expert 2008

what is the operating system?
noxchoIT Product Manager
Top Expert 2009

hanccocka gave exact steps. Follow them.

The only problem with what Hanccocka said is that the ability to increase the drive size in ESX is only when the disk is a SCSI virtual disk. If it was created as an IDE virtual disk ESX doesn't let you increase the size of the drive in vSphere. This is the drive settings for the VM and has no bearing on the physical drives.

A ran into this issue several times with WinXP VMs because their default is to have a IDE drive. It is possible to change the drive to SCSI from IDE, but it is a bit complicated.

The other issue is if there are multiple partitions on the virtual drive, you have to move the other partitions down.

Otherwise his instructions are spot on, and I have done the several thing many times.