Sun Microsystems StorageTek 9985V, Руководство пользователя

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Term Definition
Host ports DSP ports attached to hosts or host-facing SAN ports. Any DSP port is capable
of being either a host port or a storage port.
Hot-spare
Disk used by a controller unit to replace a failed disk.
Hot-swappable
A hot-swappable component can be installed or removed by simply pulling the
component out and putting the new one in. The system either automatically
recognizes the component change and configures itself as necessary or requires
user interaction to configure the system. However, in neither case is a reboot
required. All hot-swappable components are hot-pluggable, but not all hot-
pluggable components are hot-swappable.
In-band Using the data path between a host(s) and a storage device to transport system
management traffic.
Initiator
On a Fibre Channel network, typically a server or workstation that requests
transactions of disk or tape targets. Servers can have one or more initiators.
I/O
Input/output.
I/O rate
A measure of a device's capacity to transfer data to and from another device
within a given time period, typically as I/O operations per second.
IOPS Input/output operations per second. A measure of I/O performance, this is
commonly used to quote random I/O performance.
IP Internet protocol. A set of protocols developed by the United States Department
of Defense to communicate between dissimilar computers across networks.
iSCSI
A protocol being ratified by the IETF for the transmission of SCSI commands
and data blocks over TCP/IP networks .
LED
Light emitting diode.
LUN
Logical Unit as defined by SNIA. Defines a volume as it is mapped to
particular host(s) or initiator(s). Distinguished from a volume in a sense that the
same volume can represent a different LUN to different host(s) or initiator(s).
LUN mapping
Assigning volume permissions (read-only, read/write, or none) to a host or
initiator.
LUN masking
A technique that prevents all but certain initiators from gaining access to a
volume.
Management path The out-of-band path that connects components of the system to the storage
service processor.
Mirror
The process of performing write operations to multiple physical media as part of
each host-acknowledged write operation in order to maintain data availability.
Provides data integrity by keeping multiple copies of identical volume data.
Mirrored cache Redundant copies of data residing in cache — the (write) data residing in cache
that has not yet been written to the hard disks is duplicated for fail-over
operation.
Mirroring (RAID) Redundant storage of data, achieved by duplicating files (so there is always a
primary file and a copy of the primary file) onto separate disks.
Multi-pathing
Providing two or more physical paths to a given target or device.
NAS
Network Attached Storage. Network Attached Storage is a term for a
conventional or proprietary server that provides file storage over a network
using file access network protocols like NFS or CIFS.
Network terminal
concentrator (NTC) A modem connection point for the Sun StorageTek Remote Response service.
Helps facilitate a point-to-point connection from a remote support center.
Non-disruptive Does not prevent system or data access at any time during operation. Data path
access is not sacrificed, and the host does not see any I/O failure (unless dual
points of failure). May no longer a be an HA environment. Availability of
management services not included.
Non-floating hot-spare A drive that reverts back to hot-spare status after a failed drive has been
replaced and the mirror re-silvered or the stripe rebuilt.
N_Port
A Fibre Channel port in a point-to-point or fabric topology.
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