Fujitsu Primepower200 User Manual page 269

Data Packet
A sub-set of the data (including control signals) that forms a single transmission unit.
Disk Drive Bay
A (metal) frame affixed inside the server or a standalone cabinet that is designed to accept a hard
disk drive (or other, similarly sized device, e.g. CR-ROM drive, etc.).
Disk Drive Cage
A rack of disk drive bays in the server or a standalone cabinet.
Disk Formatting
Before data can be read from/written to a hard disk, the disk must have (or be given) an underlying
logical structure, or format, that the OS is able to recognize.
FEP (Front End Power unit)
The server's AC-DC power supply.
Hot-swapping
The ability to take down, remove, replace, and bring back up individual components of the system
without having to shut the system down. This allows maintenance and replacement of defective
parts to be performed even while the system continues to run, a vital ability for 24/7/365 hardware.
MAC (Media Access Control) Address
A physical (hardware) address that uniquely identifies each node of a network. For IEEE 802.3 and
Ethernet networks, it is defined as 48 bits long, with the first 24 bits being the OUI, a unique
hardware manufacturer's ID assigned by the IEEE, and the final 24 bits assigned as each
manufacturer sees fit. The absolute uniqueness of each MAC address is an important feature, and
the ROM or EPROM in most LAN devices contains such a MAC address, preventing the LAN from
being illicitly modified. A MAC address is usually represented as a string of six hexadecimal octets:
00-40-41-84-2B-2C or 00:40:41:84:2B:2C.
Memory Dump
The raw contents of a specified section of the main memory, output in hexadecimal (or the ASCII
equivalent thereof) for use in debugging.
Memory Interleaving
For speedier memory access, blocking due to wait states can be reduced by splitting the main
memory into multiple banks, making areas of memory other than that currently being addressed
more accessible. This is effective for sequential memory accesses, but gives no advantage for
random accesses.
Mirroring
Modern hard disks are highly reliable, but even so a variety of methods are used to ensure the
survival of your vitally important data, even if a disk failure does happen. One of the simplest
methods is mirroring, which basically involves keeping two copies of all data saved to the hard disk.
In this way, even if one copy is lost, the other will remain, ensuring that no data is lost.
14.1 Glossary
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