RAID Expansion and TrueCrypt

[OldSchool]

I will soon be upgrading my current 4x2TB Raid 0 to 8x2TB Raid 6. The current raid is encrypted with TrueCrypt AES, and unless someone has another suggestion I plan on using this for the new raid as well.

My concern is that I will make a mistake in the initial configuration which will come back to haunt me in the future, I am also admittedly a novice when it comes to professional level setups such as this. I am hoping that someone here has extensive knowledge of TrueCrypt and can help put me on the right path...

The system will have the following specs:

Windows Server 2008 x64
TrueCrypt 6.2a (why I am not using the latest ver will be mentioned later)
Areca 1880i RAID Controller
8x2TB Hitachi 7200rpm

Here is how I see the upgrade progressing:

1) Test all of the new hardware thoroughly (obvious)

2) Copy the current data from the Raid 0 to 2 of the new 2TB drives (there's ~4TB of data on there atm)

3) Install the Areca 1880i as well as 6x2TB Hitachis

4) Create RAID set/volume (Here is where I start to lose it, I want to use 64bit LBA so that I can have a volume larger than 16TB in the future? what are the considerations of doing this? Is there a specific stripe size that I should use? or one that I should avoid? I was thinking 64KB stripe size.)

5) Boot to Windows and format the new volume with NTFS (and again, what cluster size to use? 16K 32K? How does this relate to the stripe size that the volume is using?)

6) Encrypt the partition (Now we're getting to the meat of it. There are several ways to approach this from what I have been reading. From what I understand I could:

a) Instead of formatting the volume as previously stated I can set it as a Dynamic disk in Windows and format it as a TrueCrypt volume by selecting it as a device in the TrueCrypt configuration (I believe this formats as NTFS).

b) Create a TrueCrypt dynamic container (a file) which will reside on the previously formatted NTFS volume

I plan to use TrueCrypt 6.2a so that I can use extcv to expand the container/volume. I would like to be able to use the latest version of TrueCrypt because it supports AES hardware encryption with i5/i7, but from what I have read extcv will not work with the latest versions

All of this is geared towards servicing my requirement of a single encrypted volume that is (for all practical purposes) infinitely expandable in the future. If anyone has any better suggestions I am all ears!

7) Copy the data from the 2 temp drives over to the new encrypted raid 6 array

8) Add the 2 temp drives to the Raid controller and expand the Raid 6 volume (I would then need to wait for it to rebuild?)

9) Depending on how step # 6 went, either expand the size of dynamic partition in Windows then use extcv to expand the TrueCrypt Dynamic container, or use extcv to expand the TrueCrypt volume? There are so many layers I am starting to struggle with how they all relate...

10) **In the future** Add HP SAS expander and repeat previous expansion methods ad nauseum

Another question is, are all of these layers aware of what is below them? Do I need to use long formats so that everything is established within the full space available and data isn't accidentally overwritten? (such as using a Dynamic container in TrueCrypt which expands as files are written to it, as opposed to it creating a file the size of what is available on the partition)

As you can probably tell I am in a bit over my head, any explanations or suggestions you can offer are greatly appreciated!

 

[Ruroni]

Diskcryptor supports i5/i7 AES enhancements, and can decrypt/expand.

http://diskcryptor.net/wiki/Main_Page/en

 

[OldSchool]

It doesn't appear that you can expand the encrypted partitions with Diskcryptor, from their FAQ:

Is it safe to resize encrypted partitions?

Currently this is not supported. It is planned to include support for partition resizing with OS tools in the future.

 

[djstarfox]

Without knowing much about TrueCrypt, it might be easier for the OS if you did whole drive encryption (with pre-boot authentication).

I think you'd be much better off building a new volume with 8 drives from the beginning. Expanding/Rebuilding a 12TB volume might take days. I would ask first, what is your backup solution? Can your 4TB of data be compressed or reduced, especially since you're looking at re-installation of Windows? Is there another computer on your network that could hold the 4TB temporarily (obviously you'd have to wipe its free space afterward)?

As far as volume parameters, the ideal NTFS cluster size depends on what kind of data you're storing. For the OS only, the default 4K is fine; another example is 16K that I use for my "Games" partition.

For RAID stripe size, the ideal number depends on your drive size. In this case, I would go with the largest stripe size the RAID card will let you choose.

 

[OldSchool]

Yes unfortunately the primary motivation behind building the RAID 6 with 6 drives then expanding it is financial. As well as the requirement of having a single encrypted volume that can be expanded near limitlessly is attributable to the fact that I am a perfectionist

I am starting to realize that this goal may be at the least impractical if not impossible...

 

[Ruroni]

It was added in a new beta according to changelog.