Snapshot - Restoring a volume from Dos

Quick steps

Boot your system from a DOS boot disk.
Below it is assumed that your image data are accessible as drive W:\C-DRIVE.SNA.

If you want to (or have to) repartition your drive, because it is new or completely damaged, enter:

A:>SNAPSHOT RESTORE HD1 partitionstructure W:\C-DRIVE.SNA -Y

This will partition the whole drive (HD1) in exactly the same way as your original drive.
You don't need to do that, and shouldn't do it, if you only want to restore a single, damaged volume.

A:>SNAPSHOT RESTORE HD1 auto                    W:\C-DRIVE.SNA -Y -V

This restores all data in the automatically selected partition from the image saved on C-drive, will not ask for confirmation (-Y), and will verify that all data were indeed written correctly (-V).


Boot your system (from a DOS bootdisk)
If you don't have a DOS bootdisk available, here is more information on how to create one.

When restoring a partition, all data on it will be deleted and replaced by the data at the time of the backup.
If you think you need some of the data, you have to copy them to somewhere else before restoring the image.

After the restore, the system will be identical to the time you created the image.

To restore an image, the imagefile must be accessible to DOS (you must be able to say C:>DIR); for more information about how to access a file on CDROM, Network, or local NTFS click here.

actions to be performed

  1. show information about the hard disk's partition structure
  2. show information about the Image file
  3. restore the partition structure
  4. restore the partition data
  5. test image file for internal consistency (optional)
  6. restore Master Boot Sector (MBR) (rarely needed)

show information about the hard disk's partition structure

snapshot.exe show [HDx]

                              [HDx]:   number of hard disk, HD1 is the first hard disk


  SNAPSHOT for DOS V1.21 [Feb 27 2003] Copyright (c) tom ehlert

1 hard disk(s) detected

disk 1 - 1022 cylinders, 255 heads, 63 sectors, 512 byte
           total physical size 29314 MB

Primary partitions         start   -     end     :   start, size
 1:06 FAT16          CHS    0  1  1- 129 254 63  :     0MB,  1020MB
 2:05 extended Part.
CHS 130 0 1- 2 254 63 : 1019MB, 7037MB 3:07 NTFS inst FS CHS 3 0 1- 249 254 63 : 8056MB, 18003MB 4:0C FAT32 LBA CHS 250 0 1- 663 254 63 : 26058MB, 3248MB Logical partitions 1:06 FAT16 CHS 130 1 1- 194 254 63 : 1019MB, 510MB 2:06 FAT16 CHS 195 1 1- 324 254 63 : 1529MB, 1020MB 3:06 FAT16 CHS 439 1 1- 568 254 63 : 3443MB, 1020MB 4:07 NTFS inst FS CHS 569 1 1-1014 254 63 : 4463MB, 3499MB 5:07 NTFS inst FS CHS 1015 1 1-1015 254 63 : 7961MB, 8MB 6:04 FAT16 < 32MB CHS 1016 1 1-1019 254 63 : 7969MB, 32MB highest used sector on disk 60018840 (29307 MB)

show information about the Image file

snapshot.exe show imagefile

                              imagefile: path and name of the image file

This shows information about the saved volume as it was stored at backup time.
Additionally, the partition structure of the original disk is shown.

   A:>snapshot show  x:\c-drive.sna

Information about the saved volume from  <x:\c-drive.sna>

  Computer 'TP', drive C:, Label 'C-TP       ', Filesystem FAT (06)
  Hard disk 1 Primary Partition 1- size   2.097.393.664 =1999MB
  total size 1999 MB - 420 MB free - 32768 Bytes per cluster

disk 1 - 1222 cylinders, 255 heads, 63 sectors, 512 byte
           total physical size 9585 MB

Primary partitions         start   -     end     :   start, size
 1:06 FAT16          CHS    0  1  1- 254 254 63  :     0MB,  2001MB
 2:0F extended Part  CHS  255  0  1-1023 254 63  :  2000MB,  7586MB
Logical partitions
 1:07 NTFS inst FS   CHS  255  1  1- 514 254 63  :  2000MB,  2040MB
 2:06 FAT16          CHS  515  1  1- 641 254 63  :  4039MB,   997MB
 3:07 NTFS inst FS   CHS  642  1  1-1023 254 63  :  5036MB,  2997MB
 4:07 NTFS inst FS   CHS 1023  1  1-1023 254 63  :  8032MB,  1554MB
highest used sector on disk 19631430 (9586 MB)

restore the partition structure

This is required, if your disk is new (not partitioned), or partitioned differently.
Snapshot will restore the exact partitioning of the original disk.

The necessary information is available in each Snapshot image file.

If for some reason you want to partition the disk in a different way, you have to use FDISK or similar tools.
Note: for this to work it is necessary, that the new disk is at least as large as the partitioned area on the original disk;  Snapshot will not modify the partition information in any way.

A:>snapshot restore [HDx] partitionstructure imagefile

                                [HDx]:  Number of hard disk, starting with HD1

                                [imagefile]: Path and name of  Image file

restore the partition data

The real restore action.
This will overwrite all data on this partition and replace it with the original data.
After that, the partition is identical to the original state.

snapshot.exe restore [HDx] {auto/primary#/logical#} imagefile

                                [HDx]:  Number of hard disk

                                {auto/primary#/logical#}: automatically select the destination partition,

                                                                          or force a primary or logical partition to be restored

                                [imagefile]: Path and name of image file


Snapshot knows which partition is contained in the image file; option 'AUTO' will use this partition as the destination.
Should you want to restore a different partition, you may select this by PRIMARY1 or LOGICAL2.
Please use the SHOW command first to verify what partition you want to restore.

option  -V  ( Verify)

this will cause a verification run after the restore is completed, to verify that all data are readable and correct.
You may abort the verification at any time by pressing Ctrl-C.

Parameter -Y (Yes)

-Y  (YES) will skip the 'are you really sure' question.

the command to automatically restore the C-drive from network drive W: should look similar to:

A:\>snapshot.exe restore HD1 auto W:\ -Y -V

test image file for internal consistency

A:>snapshot test X:C-DRIVE.SNA

this reads the complete image file, and verifies readability and consistency.
This is useful, if you want to make sure, for example, that all your CDROM is readable before starting the restore.

restore Master Boot Sector (MBR)

This is rarely needed, but useful if some software installed a different boot loader in the MBR.
It will restore the very first sector on the disk.

A:>snapshot.exe restore HD1 MBR W:\

Copyright 2001-2021     Tom Ehlert Software