Gnome Partition Editor

GParted is a free partition editor for graphically managing your disk partitions. With GParted you can resize, copy, and move partitions without data loss, enabling you to:

1.  Grow or shrink your C: drive 
2.  Create space for new operating systems 
3.  Attempt data rescue from lost partitions 

 GParted main screen:

Features

Perform actions with partitions such as:

      create or delete
      resize or move
      check
      label
      set new UUID
      copy and paste

Manipulate file systems such as:

      btrfs
      ext2 / ext3 / ext4
      fat16 / fat32
      hfs / hfs+
      linux-swap
      lvm2 pv
      nilfs2
      ntfs
      reiserfs / reiser4
      ufs
      xfs

Requirements

GParted can be used on x86 and x86-64 based computers running Linux, Windows, or Mac OS X by booting from media containing GParted Live. A minimum of 128 MB of RAM is needed to use all of the features of the GParted application.

Using GParted

Go to the required VM from Vcenter and attach local ISO to the required VM.

• After that reboot the VM to use the ISO and boot off from the CD.You will go to GParted Live boot menu. 

Main screen with disk information panel.  

•  Create a new partition dialog.

• A closer look at the resize/move dialog.  

• Another look at the main window.  

Without Gnome Partition Editor

• Sometimes you may not be able to expand disk space from edit settings option on VM because the disk controller is set to IDE in the VM.In those cases try expand the disk using command line as in below exapmple for ST worker:

#cd /vmfs/volumes/G2-M610-1-SYMCLASS-SMOKETEST/10092011st110
# vmkfstools -X 20G 10092011st110.vmdk

• You will have to shutdown the VM to execute above step.Otherwise you will see below error while expanding:

/vmfs/volumes/5069d211-f615c204-bd83-0024e85a3af2/10092011st110 # cd /vmfs/volumes/G2-M610-1-SYMCLASS-SMOKETEST/10092011st101
/vmfs/volumes/5069d211-f615c204-bd83-0024e85a3af2/10092011st101 # vmkfstools -X 20G 10092011st101.vmdk
Failed to extend disk : Failed to lock the file (16392).

• Once you are done with above step you can add existing virtual disk to other VM and expand it by making secondary (in case you are having issues with diskpart for primary partition) as in below screenshot.