IBM TotalStorage NAS 300, User Reference

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client. A computer system or process that requests access to the data, services, or resources of a server (another
computer system or process). Multiple clients may share access to a common server.
client-server model. A common way to describe network services and the model user processes (programs) of
those services.
cluster. (1) A station that consists of a control unit (a cluster controller ) and the terminals attached to it. (2) A group
of APPN nodes that have the same network ID and the same topology database. A cluster is a subset of a network
identifier (NETID) subnetwork. See also
high-availability cluster multiprocessing (HACMP) and network identifier
(NETID) .
collision avoidance. In carrier sense multiple access with collision avoidance (CSMA/CA), the process of sending a
jam signal and waiting for a variable time before transmitting data. The process is designed to avoid two or more
simultaneous transmissions.
Common Internet File System (CIFS). A protocol that enables collaboration on the Internet by defining a remote
file-access protocol that is compatible with the way applications already share data on local disks and network file
servers.
connect. In a LAN, to physically join a cable from a station to an access unit or network connection point. Contrast
with attach .
CRU. See customer-replaceable unit .
customer-replaceable unit (CRU). An assembly or part that a customer can replace in its entirety when any of its
components fail. Contrast with field-replaceable unit .
D
DASD. See direct access storage device .
data bus. A bus used to communicate data internally and externally to and from a processing unit, storage, and
peripheral devices (A).
device parity protection. A function that protects data stored on a disk-unit subsystem from being lost because of
the failure of a single disk unit in the disk-unit subsystem. When a disk-unit subsystem has device parity protection
and one of the disk units in the subsystem fails, the subsystem continues to run. The disk-unit subsystem reconstructs
the data after the disk unit in the subsystem is repaired or replaced. See also
RAID .
DHCP. See Dynamic Host Configuration Protocol .
DIMM. See dual inline memory module .
direct access storage device (DASD). A mass-storage medium on which a computer stores data. Contrast with
random access memory (RAM) .
DNS. See Domain Name System .
Domain Name System (DNS). In the Internet suite of protocols, the distributed database system used to map
domain names to IP addresses.
drive bay. A receptacle in an appliance into which you insert a hard-disk-drive module. The bays are in storage units
that can be located in a different rack from the appliance.
dual inline memory module (DIMM). A small circuit board with memory-integrated circuits containing signal and
power pins on both sides of the board.
Dynamic Host Configuration Protocol (DHCP). A protocol defined by the Internet Engineering Task Force (IETF)
that is used for dynamically assigning IP addresses to computers in a network.
E
EISA. See Extended Industry Standard Architecture .
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NAS Gateway 300 User’s Reference