HP Surestore Disk Array 12h - And FC60, Advanced User'S Manual, Page: 454 / 466

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drivers on the bus, and also impedance matching to prevent signal reflections at the
ends of the cable. The SCSI bus requires termination at both ends of the bus. One end of
the SCSI bus is terminated by the adapter’s internal termination. The other end should
have a terminator placed on the 68-pin high density SCSI connector on the last SCSI
peripheral. If this device is not terminated, data errors may occur.
topology
The physical layout of devices on a network. The three Fibre Channel topologies are
fabric, arbitrated loop, and point-to-point. The disk array’s default topology is arbitrated
loop.
unbind
Unbinding reverses the LUN binding process, deleting the LUN and returning the disk
in the LUN to the unassigned disk group. Unbinding destroys all data on the LUN.
Uninterruptible Power Supply (UPS)
An Uninterruptible Power Supply is a power supply that is capable of maintaining
power even if the input ac mains supply loses its source of power.
Universal Transport Mechanism (UTM)
A special LUN reserved for communication between the host and the disk array. SCSI
commands are passed through the UTM. By default LUN 31 is used for the UTM. If the
UTM is disabled, LUN 0 is used for the SCSI command path.
VHDCI
Very high density cable interface.
volume set addressing (VSA)
An enhanced technique for addressing disk array LUNs. VSA overcomes the eight LUN
limit imposed by PDA, allowing all 32 LUNs on the disk array to be addressed by the
host.