Technical data

GL–19
Compaq HSG80 Array Controller ACS Version 8.3 Maintenance and Service Guide
ULP process A function executing within a Fibre Channel node which conforms to the
Upper Layer Protocol (ULP) requirements when interacting with other ULP
processes.
Ultra-SCSI bus A wide, Fast-20 SCSI bus.
unit A container made accessible to a host. A unit may be created from a single
disk drive or tape drive. A unit may also be created from a more complex
container such as a RAIDset. The controller supports a maximum of eight
units on each target. See also target and target ID number.
unwritten cached
data
Sometimes called unflushed data. See dirty data.
UPS Uninterruptible power supply. A battery-powered power supply guaranteed
to provide power to an electrical device in the event of an unexpected
interruption to the primary power supply. Uninterruptible power supplies are
usually rated by the amount of voltage supplied and the length of time the
voltage is supplied.
VHDCI Very high-density-cable interface. A 68-pin interface. Required for
Ultra-SCSI connections.
virtual terminal A software path from an operator terminal on the host to the controller’s
CLI interface, sometimes called a host console. The path can be established
via the host port on the controller (using HSZterm) or via the maintenance
port through an intermediary host.
VTDPY An abbreviation for Virtual Terminal Display Utility.
warm swap A device replacement method that allows the complete system remains
online during device removal or insertion. The system bus may be halted, or
quiesced, for a brief period of time during the warm-swap procedure.
Worldwide name A unique 64-bit number assigned to a subsystem by the Institute of
Electrical and Electronics Engineers (IEEE) and set by DIGITAL
manufacturing prior to shipping. This name is referred to as the node ID
within the CLI.