User`s guide

to undo changes made by the guests). In this case, you need not re-create the initial full

image, so the backup time is not crucial and the restore time will be minimal.

An incremental backup is most useful when you need frequent backups and possibility to

roll back to any one of multiple stored states. For example, let’s say you create a full

backup once a month. If you then create an incremental backup each day of a month,

you will get the same result as if you created full backups every day. However, the cost in

time and disk space (or removable media usage) will be as little as one tenth as much.

It is important to note that the above arguments are just examples for your information.

Feel free to make up your own backup policy in accordance with your specific tasks and

conditions. SonicWALL Bare Metal Recovery is flexible enough to meet any real-life

demands.

An incremental backup created after a disk is defragmented might be considerably larger

than usual. This is because the defragmentation program changes file locations on disk

and the backups reflect these changes. Therefore, it is recommended that you re-create

a full backup after disk defragmentation.

3.3 SonicWALL Universal Restore

3.3.1 SonicWALL Universal Restore purpose

A system disk image can be deployed easily on the hardware where it was created or to

identical hardware. However, if you change a motherboard or use another processor

version — a likely possibility in case of hardware failure — the restored system could be

unbootable. An attempt to transfer the system to a new, much more powerful computer

will usually produce the same unbootable result because the new hardware is

incompatible with the most critical drivers included in the image.

Using Microsoft System Preparation Tool (Sysprep) does not solve this problem, because

Sysprep permits replacing drivers only for Plug-and-Play devices (sound cards, network

adapters, video cards etc.). As for system Hardware Abstraction Layer (HAL) and mass

storage device drivers, they must be identical on the source and the target computers

(see Microsoft Knowledge Base, articles 302577 and 216915).

SonicWALL Universal Restore technology provides an efficient solution for hardware-

independent system restoration by replacing the crucial Hardware Abstraction Layer (HAL)

and mass storage device drivers.

SonicWALL Universal Restore is applicable for:

1. Instant recovery of a failed system on different hardware

2. Hardware-independent cloning and deployment of operating systems

3. Real-to-virtual and virtual-to-real computer migration for system recovery, test and

other purposes.

3.3.2 SonicWALL Universal Restore general principles

1. Automatic HAL and mass storage drivers selection

SonicWALL Universal Restore searches the Windows default driver storage folders (in the

image being restored) for HAL and mass storage device drivers and installs drivers that

better fit the target hardware. You can specify a custom driver repository (a folder or

folders on a network drive or CD) which will also be used for drivers search.