Glossary
B
Backup devices
and slots
See Virtual Tape Devices.
C
CIFS
Common Internet File System. The protocol used in Windows environments for shared folders.
D
Deduplication
Data deduplication compares blocks of data being written to the backup device with data blocks
previously stored on the device. If duplicate data is found, a pointer is established to the original
data, rather than storing the duplicate data sets. This removes, or 'deduplicates' the redundant
blocks.
The main benefit of deduplication is that it is possible to store more data and retain data for
longer on each device. The host using the device has access to a greater depth of historical data
that would otherwise have been archived offline.
E
Emulation types
HP StoreOnce products emulate a range of physical Tape Autoloaders or Tape Libraries. Supported
emulation types are listed below:
•
HP MSL2024 Library
•
HP MSL4048 Library
•
HP MSL8096 Library
•
HP ESL-E Library
•
HP EML-E Library
•
HP D2DBS Generic Library
If it is supported by your backup application, HP D2DBS Generic Library is the preferred emulation
type because it does not emulate any physical library types in existence and is clearly identifiable
as a StoreOnce device. It is the most flexible emulation type available; however, backup
application support varies by software vendor.
F
Fibre Channel (FC)
Fibre Channel (FC) supports network connectivity over fibre optic cabling or copper wiring. FC
has a different set of standards and network connection protocol to Ethernet and different
configuration requirements. FC HP StoreOnce Backup Systems may be connected to both a Fibre
Channel SAN and an Ethernet (as an iSCSI device) network. The FC connection is used only to
transfer backup data from the host to the HP StoreOnce Backup System. Access to the Web
Management Interface is always across an Ethernet connection.
H
Hosts
A server that is being used to back up to the StoreOnce system via iSCSI or Fibre Channel, this
may also be a backup application media server which can back up other servers on the network
that do not have a direct iSCSI or Fibre Channel connection to the StoreOnce Backup System.
Housekeeping
If data is deleted from the StoreOnce system (e.g. a virtual cartridge is overwritten or erased),
any unique chunks will be marked for removal, any non-unique chunks are de-referenced and
their reference count decremented. The process of removing chunks of data is not an inline
operation because this would significantly impact performance. This process, termed
'housekeeping' runs on the appliance as a background operation, it runs on a per cartridge and
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