ServerNet Cluster 6780 Planning and Installation Guide (G06.24+, H06.03+)

Glossary
ServerNet Cluster 6780 Planning and Installation Guide—527301-004
Glossary-5
cyclic redundancy check (CRC)
Class 2, and Class 3 according to the risk of causing a system outage if the
documented replacement procedure is not followed correctly and how much
CRU-replacement training or experience is advisable. See also field-replaceable unit
(FRU).
cyclic redundancy check (CRC). The most widely used error detection code for ensuring
the integrity of transmitted data. The digits of the CRC are calculated by the sender for
each block of data sent and recalculated by the receiver. It is a family of mathematical
functions involving computing the quotient and remainder of a polynomial division. A
CRC is a form of checksum. See also checksum.
dedicated LAN. An Ethernet LAN for use only by OSM applications. This LAN connects
system consoles with the Ethernet ports on the processor multifunction (PMF) CRUs in
group 01 of a NonStop S-series server. A dedicated LAN supports NonStop S-series
servers and system consoles but does not support any other types of servers or
workstations. See also public LAN.
Dense Wave Division Multiplexer (DWDM). A hardware device that converts multiple
optical signals into different wavelengths or optical channels. A DWDM can save on
fiber costs by transmitting multiple channels over a single fiber.
destination ServerNet ID (DID). A field in the ServerNet packet header indicating the
intended destination for the packet.
detailed report. A complete listing of status or configuration information provided by the
Subsystem Control Facility (SCF) STATUS or INFO command when you use the
DETAIL option. Contrast with summary report
dial-out point. A system console from which incident reports are sent to a service provider.
Incident reports are sent only from the system consoles defined as the primary and
backup dial-out points.
DID. See destination ServerNet ID (DID)
.
discovery. For the OSM package, the process of identifying the resources that exist on a
NonStop S-series server.
disk drive. A device that stores and accesses data on a disk. The two types of disk drives
are magnetic and optical. Random access to addressable locations on a magnetic disk
is provided by magnetic read/write heads. Random access to addressable locations on
an optical disk is provided by a low-intensity laser. Optical disk drives are not
supported for NonStop S-series servers. See also volume
.
DNS. See Domain Name System (DNS).
DNS server. A server that resolves hostnames to Internet protocol (IP) address mapping
queries. These queries originate either from client computers, which are known as
resolvers, or from other Domain Name System (DNS) servers, which accounts for the
distributed nature of DNS. See also Domain Name System (DNS) and node.