Author Topic: Risks of data corruption  (Read 2172 times)

Mazely

  • Newbie
  • *
  • Posts: 4
Risks of data corruption
« on: November 09, 2008, 12:21:04 am »
I did a small test, on a dedicated primary partition (NTFS). I compared the size of the partition before first encryption, then while encrypted and mounted, then while decrypted.

And I always got the same 'Capacity' (in bytes), the same 'Used space' (in bytes) and the same 'Free space' (in bytes).

So I wonder where does the header go? Why does the header don't seem to take any place?
Shouldn't be the partition shrunk in order to let some place to the header (like TC does)?

Which leads to the question : is there any risk of data corruption with DC?


ntldr

  • Administrator
  • Hero Member
  • *****
  • Posts: 1079
Re: Risks of data corruption
« Reply #1 on: November 09, 2008, 08:34:05 am »
Quote
So I wonder where does the header go? Why does the header don't seem to take any place?
Hmm, partition should be shrinked (please unmount/mount partition to check this because file system did not immediately see the changes).

Quote
Shouldn't be the partition shrunk in order to let some place to the header (like TC does)?
encryption partition with existing data in TC is not working in many situations. TC use FSCTL_SHRINK_VOLUME ioctl to change volume size, this is safe, but it works only in Windows Vista. DC use FSCTL_SHRINK_VOLUME in Vista and manual FS header manipulation in other OS. This may be unsafe, because NTFS file system is not documented, but this is works on non-Vista systems.
If you format new volume with "dccon -format", DC create volume headers before FS created, this is works safe.

ntldr

  • Administrator
  • Hero Member
  • *****
  • Posts: 1079
Re: Risks of data corruption
« Reply #2 on: November 09, 2008, 08:39:38 am »
Next DC will use own volume format without TC compatibility. This will make safe encryption on any OS.

Mazely

  • Newbie
  • *
  • Posts: 4
Re: Risks of data corruption
« Reply #3 on: November 09, 2008, 05:45:54 pm »
You were right, unmounting and mounting the volume again did the trick. Thanks.