IBM TotalStorage FAStT600, Installation And User Manual

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RDAC. See redundant dual active controller .
redundant dual active controller (RDAC). A
controller, used with AIX and Solaris hosts, that provides
a multipath driver for a storage subsystem. An RDAC is
also known as redundant disk array controller.
red, green, blue (RGB). (1) Color coding in which the
brightness of the additive primary colors of light, red,
green, and blue are specified as three distinct values of
white light. (2) Pertaining to a color display that accepts
signals that represent red, green, and blue.
RGB. See red, green, blue .
ROM. See read-only memory .
router. A computer that determines the path of
network traffic flow. The path selection is made from
several paths based on information obtained from
specific protocols, algorithms that attempt to identify the
shortest or best path, and other criteria such as metrics
or protocol-specific destination addresses.
SAN. See storage area network .
SCSI. See small computer system interface .
segmented loop ports (SL_Ports). SL_Ports allow
you to divide a Fibre Channel Private Loop into multiple
segments. Each segment can pass frames around as
an independent loop and can connect through the fabric
to other segments of the same loop.
serial storage architecture (SSA). An interface
specification from IBM in which devices are arranged in
a ring topology. SSA, which is compatible with SCSI
devices, allows full-duplex packet multiplexed serial data
transfers at rates of 20Mb/sec in each direction.
server. A functional hardware and software unit that
delivers shared resources to workstation client units on
a computer network.
server/device events. Events that occur on the server
or a designated device that meet criteria that the user
sets.
Simple Network Management Protocol (SNMP). In
the Internet suite of protocols, a network management
protocol that is used to monitor routers and attached
networks. SNMP is an application layer protocol.
Information on devices managed is defined and stored
in the application’s Management Information Base
(MIB).
SL_Port. See segmented loop ports .
small computer system interface (SCSI). A standard
hardware interface that enables a variety of peripheral
devices to communicate with one another.
SNMP. See Simple Network Management Protocol .
SNMPv1. The original standard for SNMP is now
referred to as SNMPv1, as opposed to SNMPv2, a
revision of SNMP. See also
Simple Network
Management Protocol .
SNMP time-out. The maximum amount of time the
SANavigator tool will wait for a device to respond to a
request. The specified time applies to one retry only.
SNMP trap events. SNMP is based on a
manager/agent model. SNMP includes a limited set of
management commands and responses. The
management system issues messages that tell an agent
to retrieve various object variables. The managed agent
sends a Response message to the management
system. That message is an event notification, called a
trap, that identifies conditions, such as thresholds, that
exceed a predetermined value.
SRAM. See static random access memory .
SSA. See serial storage architecture .
static random access memory (SRAM). Random
access memory based on the logic circuit known as
flip-flop. It is called
static because it retains a value as
long as power is supplied, unlike dynamic random
access memory (DRAM), which must be regularly
refreshed. It is however, still volatile, meaning that it can
lose its contents when the power is switched off.
storage area network (SAN). A network that links
servers or workstations to disk arrays, tape backup
subsystems, and other devices, typically over fibre
channel.
storage management station. A system that is used
to manage the storage subsystem. A storage
management station does not need to be attached to
the storage subsystem through the fibre-channel I/O
path.
subnet. An interconnected but independent segment
of a network that is identified by its Internet Protocol (IP)
address.
super video graphics array (SVGA). A video display
standard that Video Electronics Standards Association
(VESA) created to provide high resolution color display
on IBM PC compatible personal computers. The
resolution is 800 x 600 4-bit pixels. Each pixel can
therefore be one of 16 colors.
SVGA. See super video graphics array .
sweep method. A method of sending SNMP requests
for information to all the devices on a subnet by sending
the request to every device on the network. Sweeping
an entire network can take a half an hour or more. If
broadcast is disabled, the recommended method is to
enter the individual IP addresses of the SAN devices
into the SANavigator tool. This method produces good
results without unnecessarily using time to wait for
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IBM TotalStorage FAStT600 Fibre Channel Storage Server: Installation and User’s Guide