HP NonStop G-Series - Manual (Page 277)

The star groups are joined by two-lane links. The tri-star topology supports up to 24
nodes. See also
split-star topology , star topology , and layered topology .
two-lane link
The two single-mode fiber-optic (SMF) ServerNet cables that connect the HP NonStop
Cluster Switches on the same external fabric (for example, X1, X2, and X3) in a
tri-star
topology .
U
unattended site (dark site)
A location where no operator is working on site and the only access to the LAN is from a
centralized monitoring station through a modem connected to a routing workstation . Dark
site is a synonym for unattended site.
uncorrectable memory error (UCME)
An error caused by incorrect data at a particular memory location. The cause of the
incorrect data is one that is not automatically corrected by the system, and memory
replacement might be required. The occurrence of a UCME indicates that a processor is
having memory errors. The processor halts with a hardware error freeze and generates an
alarm as well as an incident report .
uninterruptible power supply (UPS)
The equipment used to provide an uninterruptible source of power to connected
equipment if a main power outage occurs. The basic components of any UPS system are
a rectifier/charger that converts alternating-current (AC) power to direct-current (DC)
power, batteries that store the DC power, and an inverter that converts the DC power
back into AC power for distribution to the load..
V
value-added diagnostics
A collection of troubleshooting and support features that are included with a valid service
contract. These features include:
The generation of incident reports and EMS event messages related to incident
reports ●
The ability to configure the dial-out phone number ●
Support for dial-in on a system console ●
Recommended repair actions associated with alarms ●
vertical tetrahedron