Glossary - Intergraph InterRAID-8e Hardware User's Manual

Glossary

Advanced Technology (AT)
A class of computers and processors using the 80286 microprocessor and 16-bit bus.
asynchronous operations
Operations that have no relationship to each other in time and can overlap. The
concept of asynchronous I/O operations is central to independent access arrays in
throughput-intensive applications.
bad block table
A table of information on bad blocks encountered during the rebuild and write-back
processes of hard disk drives in a RAID system.
Basic Input Output System (BIOS)
A program permanently stored in the flash EPROM on the server mother board, or
in the flash EEPROM on the RAID controller board.
boot disk drive
The RAID disk drive(s) containing the operating system.
cache
A high-speed memory buffer that contains the most recently accessed data from the
DRAM memory system.
cache flush
An operation where all unwritten blocks in a write-back cache are written to the
target disk. This operation is necessary before powering down the system.
channel
An electrical path for the transfer of data and control information between a disk
and a disk controller.
consistency check
The process whereby the integrity of redundant data is verified. For example, a
consistency check of a mirrored drive will ensure the data on both drives of the
mirrored pair are exactly the same.
disconnect/reconnect
A function to allow a target SCSI device (typically a disk drive that received a
request to perform a relatively long I/O operation) to disconnect the SCSI bus so
that the controller can send commands to other devices. When the operation
completes and the SCSI bus is needed by the target device again, it is reconnected.
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