IBM i 830, Repair Manual

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dedicated service tools. The part of the service
function used to service the system when the operating
system is not working.
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 system continues to run. The disk
unit subsystem reconstructs the data after the disk unit
in the subsystem is repaired or exchanged.
DFCI. Disk file control interface.
DIMM. Dual in-line memory module.
disk enclosure. The part of a disk unit that contains
the read and write heads, the magnetic disks, and the
actuators.
download. To transfer data from a processing unit to
an attached device, such as a microcomputer, for
processing.
DST. Dedicated service tools. The part of the service
function used to service the system when the operating
system is not working.
EMC. Electromagnetic compatibility.
EMI. Electromagnetic interference.
EPO. Emergency power-off.
ERC. Extended reference code
ESD. Electrostatic discharge.
expansion unit. An expansion unit contains I/O
hardware such as cards, tapes and disk units. The
system may have multiple expansion units.
An expansion unit can be bolted directly to the side of
a system unit and is contained within the system unit
covers.
An expansion unit can also be mounted on top of a
rack or tower and has its own covers.
Internal signal cables interconnect the expansion unit to
the system unit, rack, or tower.
FAX. Facsimile machine.
FC. Feature code.
FDS. Flexible distribution system.
FRU. Field-replaceable unit.
GND. Ground (electrical).
Guest partition. This is a secondary partition which is
running an operating system other than OS/400. The
guest partition requires another partition to host it. The
purpose of the hosting partition is to supply paths from
virtual I/O in the guest partition’s operating system to
real I/O hardware drivers in the hosting partition. The
guest partition requires a console in order to provide
an interface to DST console functions. TELNET is used
to establish a guest console from the hosting partition.
The guest partition’s console should not be confused
with the console used by the operating system running
in the guest partition. They are separate console
sessions.
high-speed link (HSL). A hardware connectivity
architecture that links system processors to
input/output processors (IOPs) and other system units.
Hosting partition. This is a partition, either the
Primary or a secondary partition that is not a guest
partition. The hosting partition has the real I/O devices
that the virtual I/O device drivers in a guest partition
connect to. The hosting partition also supplies the guest
partition’s DST console session, via a TELNET
connection into the hosting partition. The guest
partition’s console is not part of the hosting partition’s
console. The host partition’s console, the guest
partition’s console session and the guest partition’s
operating system’s console are all different console
sessions.
HSL Ring. High Speed Link Ring (shown as
″
System
Interconnect
″
on the display). This is a logical ring of
HSL connections originating from the HSL Controller of
a processor unit, sequentially connecting I/O or other
processor units and ending back at the HSL Controller
where the ring originated.
ID. Identification.
input/output processor. A device that processes
programmed instructions and controls one or more I/O
devices or adapters.
I/O. Input/output.
IOA. Input/output adapter.
IOP. Input/output processor. A device that processes
programmed instructions and controls one or more I/O
devices or adapters.
IPL. Initial program load.
IXA. Integrated xSeries Adaptor (IXA)
IXS. Integrated xSeries Server (IXS)
LAN.
Local area network. A computer network
located on a user’s premises within a limited
geographical area.
LIC. Licensed Internal Code.
license. A permission granted by competent authority
to engage in a business or occupation or in an action
otherwise unlawful.
Glossary
980
iSeries Model 830, 840, SB2, and SB3 Problem Analysis, Repair and Parts V5R1