Is it safe to Restore an disc image to an imitation drive.

[alan_b]

I wish to restore a disc image of C:\ to an external USB drive.
Drive C:\ Properties are NTFS and
Used Space 7.43 GB
Free Space 10.7 GB
Capacity 18.1 GB

I would like to restore to a TrueCrypt mounted volume/partition,
or even to a DOS SUBST "virtual" drive.

Can I do this without danger / deletion / erasure of files that already exist on the partition which holds the imitation Truecrypt/SUBST drive ?

Background :-

The external drive has several large partitions, some are NTFS, some are FAT32.
Purely academic interest - would it cause problems to restore onto a FAT32 partition ?

I only have 13 GB of free space so I cannot restore the complete 18.1 GB partition, therefore I believe that after Archive Selection when I choose Restoration type I need "Restore specified files or folders".

Then for Destination I can choose "New - restore absolute paths".
I am then allowed to choose any destination, including :-
F_5_Gig (F:) Folder F:\ Local Disc:- Free Space 1.717 GB:- Total Size 5.355 GB
J_BACKUP (P:) Folder P:\ Local Disc:- Free Space 4.214 GB:- Total Size 105.4 GB
K_BACKUP (Q:) Folder Q:\ Local Disc:- Free Space 3.678 GB:- Total Size 94.69 GB
Local Disc (R:) Folder R:\ Local Disc:- Free Space 9.714 GB:- Total Size 9.766 GB

F:\ is a genuine 5 GB partition on the external drive. The other 3 are "special".
P: and Q: were created with the DOS command SUBST upon folders in proper external partitions J: and K: respectively.
R: is a TrueCrypt mounted/encrypted volume using another folder in K:

I am allowed to select any one of the 4 destinations, and can click through to the final PROCEED without any warnings, even though it is obvious that 7.43 GB of C:\*.* files will not fit into anything other than R: with 9.714 GB.

It is obvious that no validation of the destination is performed before I click PROCEED..
Is any validation performed afterwards ?

Will Acronis happily blow a fuse trying to fit 7.43 GB into 5.355 GB in F:\ ?

If I restore to P:\ or Q:\ will Acronis happily delete some, or even ALL, of the already existing files present on J:\ or K:\ ?

I appreciate that I can use a partition manager to take some free space out of K: and create a new partition L: and Acronis should be able to restore all files and folder to that without any danger to any files in other partitions on the external drive.

Unfortunately I was using computers before there was Windows, and it was considered prudent to use a stack of floppy discs to back-up C:\ before de-fragmenting it, and if partitioning was attempted that almost guaranteed you would afterwards have to restore the system from the stack of floppies.

I still have a nervous twitch when the LEDs indicate that de-fragmentation is in progress.
I am hoping to never ever risk using a Partition Manager.

My most important question, can I use TrueCrypt R: without damaging the many other files and folders in K: ?

Regards
Alan

[seekforever]

You've got a lot of questions in the post. My first impression is that hoping TI will understand DOS Subst commands and a TrueCrypt pseudo-disk is very unlikely. TI has to recognize and understand the file system when it does a backup or restore and if there is any intervening trickery it makes less likely.

When TI restores a partition one of the first things it does is delete the partition which means everything in it is gone. If the partition data is too big to fit onto the partition receiving the restore it cannot be restored. This refers to the actual used space, not the total size of the backed up partition.

TI does not support encrypted disks for the reason above and the only way it can back up an encrypted disk is by doing a sector-by-sector backup which means every sector on the encrypted partition, used or unused. This takes more space and time.

The TI rescue environment for the active partition is Linux whether you start the restore from Windows or the rescue CD. If started in Windows the PC will reboot into TI's Linux environment. This means that some of the things Windows might understand or have a good driver for, may not be equally supported by the Linux stuff.

An image backup of your disk would backup the Cryptainer "disk" since it exists as a file. You may be able to restore it like any other file and then your Cryptainer software should find and mount it one would think.

If you don't get more definitive answers the best thing for you to do would be to invest in another drive and do some testing for your setup.

[alan_b]

Originally Posted by seekforever

When TI restores a partition one of the first things it does is delete the partition which means everything in it is gone.

I did read in the help manual that restoring a partition would first delete the existing destination partition,
but I was hoping that restoring only folders and files would not damage the existing destination.

Windows seems to deceive Acronis into describing these "virtual" partitions as "Local Drives" in exactly the same way as it describes genuine partitions, so I think I might be lucky - especially if I aim at the rigidly fixed size 9.766 GB drive R:\.

As a design engineer I always anticipated and guarded against potential problems before releasing a design to production.

I am stuck with that habit now I am retired, so unless anyone posts a powerful assurance I will go along with your suggestion - and if the children club together another drive will be much better than boxes of chocolates for Christmas !!!

NB I am not really concerned about the accuracy of restoring to a "virtual" partition. I am very concerned that nothing shall go wrong outside the "virtual" boundaries.

I only want to detect any junk accumulated on C:\ since the last image was created, so I may then purge from C:\ the junk I don't want before I create the next archive.
Till now I have simply mounted the last image and compared C:\ with the mounted image, but I am now looking for any alternative to mounting an image, having discovered this leads to damage with unknown consequences, as per my post
http://www.wilderssecurity.com/showthread.php?t=226443

Regards
Alan