User guide

H
HA High availability. A system or device that operates continuously for a long length of time.
HDLM Hitachi Dynamic Link Manager
HDS Hitachi Data Systems
HIT Host Integration Tools
I
initiator A sSystem component, such as a network interface card, that originates an I/O operation.
IQN iSCSI qualified name
iSCSI Internet small computer system interface. Transmits native SCSI over the TCP/IP stack. In a system
supporting iSCSI, a user or software application issues a command to store or retrieve data on
a SCSI storage device. The request is processed by the operating system and is converted to one
or more SCSI commands that are then passed to software or to a card. The command and data
are encapsulated by representing them as a serial string of bytes proceeded by iSCSI headers.
The encapsulated data is then passed to a TCP/IP layer that breaks it into packets suitable for
transfer over the network. If required, the encapsulated data can also be encrypted for transfer
over an insecure network.
iSNS Internet storage name service. Used for discovery and management of IP-based SANs.
J
jumbo frames Large IP frames used in high-performance networks to increase performance over long distances.
Jumbo frames are typically 9,000 bytes for GbE, but can refer to anything over the IP MTU (1,500
bytes on an Ethernet).
L
LBA Logical block address
load balancing Adjusting components to spread demands evenly across a system’s physical resources to optimize
performance.
LUN Logical unit number. Representation of a logical address on a peripheral device or array of
devices.
M
MMC Microsoft Management Console
MPIO Multipath I/O
MSA HP StorageWorks Modular Storage Array
MTU Maximum transmission unit. The size (in bytes) of the largest packet that a specified layer of a
communications protocol can transfer.
multipath routing The routing technique of leveraging multiple alternative paths through a network, which can yield
a variety of benefits such as fault tolerance, increased bandwidth, or improved security.
N
NAA Name address authority.
NPIV N_Port ID virtualization
NTP Network time protocol. Used for distributing the Coordinated Universal Time by synchronizing
the clocks of computer systems over data networks.
P
P2P Port to port.
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