Administrator's Guide

20 HP StorageWorks EVA Fast Recovery Solution for Windows Server 2003: Administration Guide
Exchange
Exchange runs on the Producton Server and writes data to primary disk
array volumes. FRS protects Exchange by creating and managing shadow
copies of Exchange storage groups.
Software components called “writers” interface with Exchange to
coordinate volume shadow copy creation. Some operating system writers
come with Windows, while others, such as the Exchange writer, come with
the application software.
Upon request from FRS for a shadow copy, the writer flushes the
application buffers and holds I/O to the application. It then notifies the VSS
hardware provider that it is ready for a shadow copy, and the VSS HWP
copies the production volume to a recovery volume. When the copy is
complete, VSS releases the application to resume normal operation. This
process ensures consistent data even though the application is still running.
FRS
FRS consists of two sets of components: one set of production server
components, and a separate set of recovery server components, including a
graphical user interface. FRS as a whole is referred to by Microsoft as a
“requestor” application that requests service from VSS.
The FRS GUI runs on the recovery server and provides user control of FRS
on the production server. You can use the FRS GUI to make shadow copies
of the data on the production LUNs, and use the GUI to recover the
complete dataset from a copy on the recovery LUNs.
FRS on the production server interacts with the Windows VSS service and
HP Hardware Provider (HWP). When FRS requests it, this service and
provider combination coordinates with the writer and application to create a
volume shadow copy of the production data on the production array LUNs.
The complete recovery-ready copy is placed on recovery array volumes.
FRS presents the recovery volumes to the recovery server through VSS.
This enables you to use the recovery server to archive the recovery data to
backup tapes at any time. In the event of production data corruption, you