HP 12000 User Manual page 197

RAID1-level data A RAID that consists of at least two drives that use mirroring (100 percent duplication of the
storage storage of data). There is no striping. Read performance is improved since either disk can be
read at the same time. Write performance is the same as for single disk storage.
RAID5-level data A RAID that provides data striping at the byte level and also stripe error correction information.
storage RAID5 configurations can tolerate one drive failure. Even with a failed drive, the data in a RAID5
volume can still be accessed normally.
RAID6-level data A RAID that provides data striping at the byte level and also stripe error correction information.
storage RAID6 configurations can tolerate two drive failures. Even with two failed drives, the data in a
RAID6 volume can still be accessed normally. RAID6 read performance is similar to RAID5, since
all drives can service read operations, but the write performance is lower than that of RAID5
because the parity data must be updated on multiple drives.
redundancy In a redundant system, if you lose part of the system, it can continue to operate. For example, if
you have two power supplies with one that takes over if the other one dies, that's redundancy.
replication The process of writing data to virtual tape, and after the backups are complete, writing the data
to another virtual tape, known as the replication target, over the LAN/WAN. Similar to
automigration.
S
SAN Storage area network. A network of storage devices available to one or more servers.
SATA Serial Advanced Technology Attachment.
SCSI Small Computer Systems Interface. A standard, intelligent parallel interface for attaching peripheral
devices to computers, based on a device-independent protocol.
secondary node A computer (node) that provides secondary administrating and control for backup and restore
operations on a server cluster, and provides additional storage and multi-pathing capabilities on
the system.
smart copy A software feature within the automigration process that is under the control of the backup
application and managed via the VLS device's SMI-S interface. This requires the backup application
to support the HP smart copy interface. (Smart copy is similar to snapshot.)
SMI-S Allows control of the virtual tape library by a connected destination library for the purpose of
implementing automigration. SMI-S support allows applications attached to the VLS to detect the
virtual library configuration and to allow some users to change the state of the VLS.
SNMP Simple Network Management Protocol. A widely used network monitoring and control protocol.
Data is passed from SNMP agents, which are hardware and/or software processes reporting
activity in each network device (hub, router, bridge, and so on) to the workstation console used
to oversee the network. The agents return information contained in a MIB (Management Information
Base), which is a data structure that defines what is obtainable from the device and what can be
controlled (turned off, on, and so on).
SSL certificate Secure Sockets Layer certificate. A protocol designed to enable applications to transmit information
back and forth securely. Applications that use this protocol inherently know how to give and
receive encryption keys with other applications, as well as how to encrypt and decrypt data sent
between the two.
Some applications that are configured to run SSL include web browsers like Internet Explorer and
Netscape, mail programs like GroupWise, Outlook, and Outlook Express, FTP (file transfer
protocol) programs, etc. These programs are automatically able to receive SSL connections.
To send an SSL connection, however, or to open a secure connection, your application must first
have an encryption key assigned to it by a Certification Authority. Once it has a unique key of
its own, you can establish a secure connection with every other application that can "speak" the
SSL protocol.
storage pool Multiple disk arrays logically grouped together from which the dynamic disk filesystem allocates
storage. The disk arrays in a VLS are automatically configured into one storage array.
T
tape drive (1) A device that reads data from and writes data onto tape.
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