User manual

As the name infers, offline data processing can only be accomplished when the data is in consistent state (the operating

system and all the applications are completely shut down). Actually it is the most preferable way of image creation or

data cloning, since software can obtain an exclusive right to process data that guaranties high level of operating

efficiency. However, the offline data processing is absolutely out of question when dealing with 24/7 production

environments.

In contrast, online data processing enables to create a consistent snapshot even as the data is currently modified. It is

particularly useful for systems with high availability requirements, but it won’t be accomplished until all active

transactions are complete. The point is to provide a coherent state of all open files and databases involved in a process,

taking into account that applications may still keep writing to disks. As a result an online data processing cannot boast

high operating speed.

Our program supports both offline and online methods of data processing. As far as online method is concerned it offers

its own hot processing algorithm together with the possibility to use snapshot technologies provided by the Microsoft

VSS framework.

Paragon Hot Processing Technology

Paragon Hot Processing is an online copy/backup technology for Windows NT+ family operating systems. Developed

back in 2001, nowadays it is integrated with all copy/backup solutions offered by the company.

Paragon Hot Processing is not exactly a snapshot technology, though it has much in common with it. During an online

copy/backup, the program uses the kernel mode driver HOTCORE.SYS to intercept and control disk write activity of

applications and the operating system. The hotcore driver as an integral part of the program is installed during the setup

procedure (that’s why the system reboot is required to complete the setup procedure). For the most part the driver is in

the idle mode until it is activated with the program. While in this mode it bypasses any calls having no effect on the

overall system performance, but a few kilobytes of the system memory.

Paragon Hot Processing technology offers copy/backup of locked partitions and hard disks under Windows NT+ family

operating systems providing both high operating efficiency as well as low hardware requirements.

It is not recommended to use Paragon Hot Processing with active SQL Server, Exchange or

Oracle databases since the backup image contents may be corrupted.

Volume Shadow Copy Service

Microsoft Volume Shadow Copy Service (VSS) is designed to provide the copy/backup infrastructure for the Microsoft

Windows XP/Vista/Server 2003/2008 operating systems. It offers a reliable mechanism to create consistent point-in-

time copies of data known as shadow copies. Developed by Microsoft in close cooperation with the leading

copy/backup solution vendors on the market, it is based on a snapshot technology concept.

Initiated by a VSS aware copy/backup utility, VSS creates snapshots for the selected volumes and represents them as

virtual read-only devices, called volume shadow copies. Once the shadow copies are created, the copy/backup utility

starts processing the data while applications keep writing to original volumes.

Unlike Paragon Hot Processing the VSS technology provides a unique possibility to make a synchronous snapshot of

multiple volumes. This very feature can be particularly beneficial when backing up active SQL Server 2003, Exchange

2003 or Oracle databases located on multiple volumes the way it is recommended by Microsoft to improve the level of

database performance and reliability, thus providing 100-percent data consistency.