User manual

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Copyright© 1994-2010 Paragon Software Group. All rights reserved.
3. Please note drivers are not cached during selection. That’s why if you select a driver to add to the system, but
it’s already unavailable during the operation, the program will end the operation with an error.
Paragon Hot Processing & Volume Shadow Copy Service
Offline versus Online Data Processing
In the course of time there have been developed various methods of data processing. Despite different work concept,
all of them can be divided into two principal groups: offline (cold) and online (hot) data processing techniques.
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.