virtualbox.org

Recently converted a machine into Virtualbox.
Unfortunately the disk was 80GB but with only about 5 used.
The problem is my VDI is about 10GB (kinda useless since the data is 5GB only)

What is the easiest way to shrink the partition inside the VDI?

You have two choices:
1) Periodic compact: (optional) Defrag, Zero free space, VBoxManage modifyhd ... --compact. (Do these steps in the VM:)

• Backup!
• (Optional, can help with defragmentation) Delete the USN Journal:
  (May interfere with badly written search or archive programs.)

  Code: Select all

  fsutil usn deletejournal /n c:

  http://www.mydefrag.com/VolumeActions-D ... urnal.html
• (Optional) Compact/Defrag the disk, to push all free space to the end.
• Clear all free space to zero (this helps greatly with VB compaction of standard=Dynamically sized VDIs).

  Code: Select all

  sdelete -c c:

  http://technet.microsoft.com/en-us/sysi ... 97443.aspx
• Compact

  Code: Select all

  VBoxManage modifyhd <VDIname> --compact

2) Repartition, followed by periodic compact as above

• Backup!
• (Optional, can help with defragmentation) Delete the USN Journal:

  Code: Select all

  fsutil usn deletejournal /n c:

• (Optional) Compact/Defrag the disk, to push all free space to the end.
• Clear all free space to zero (this helps greatly with VB compaction of standard=Dynamically sized VDIs).

  Code: Select all

  sdelete -c c:

• Use EASUS Partition Manager to resize the partition.
  http://www.partition-tool.com/easeus-pa ... tition.htm
  (You probably won't be able to repartition the currently booted partition, so either attach the hard disk to a VM as a non-boot disk and run partition manager from there, or use a UBCD4Win ISO (http://www.ubcd4win.com/), which includes EASUS Partition Manager as part of its download.)
• Boot the VM, and let it do an AutoChk/ChkDsk (it it does not, then manually CHKDSK /f the drive).

Hey Mark, you've helped me often in the past, of which I'm grateful. I believe your code is incorrect. With sdelete switches are preceded with a dash and not a slash i.e. sdelete -z C:

Another thing, -z is for cleansing and empty space is overwritten with random data, not zeros (As I understand the information published on the SysInternals Website). The correct command would be sdelete -c C:. One more thing, to run sdelete within the VM, the previous command didn't work for me, only sdelete -c works.

Best regards,

Etepetete wrote:I believe your code is incorrect.

Thank you for correcting me!

After some investigation, I have found the following:

• -z writes random data (3 times) to clean a disk, as you say (I have corrected my post above).
• -c writes zero data (1 times) to zero a disk, very useful for compressing a disk.
• sdelete accepts either /x style options or -x style options.
• The sdelete doc says "sdelete [-p passes] [-z|-c] [drive letter]", BUT the ':' character after the drive letter is required.

... -Z Cleaning and -C Zeroing (swapped) I thought must have been a documentation mistake!