NonStop S-Series Server Description Manual (G06.24+)

Glossary
HP NonStop S-Series Server Description Manual—520331-003
Glossary-25
Domain Name System (DNS)
(2) In a NonStop S-series server, a pair of service processors, the associated router
clouds, and the attached replaceable units.
(3) A set of objects over which control or ownership is maintained. Types of domains
include power domains and service processor (SP) domains.
Domain Name System (DNS). A system that defines a hierarchical, yet distributed,
database of information about hosts on a network. The network administrator
configures the DNS with a list of hostnames and Internet protocol (IP) addresses,
allowing users of workstations that are configured to query the DNS to specify remote
systems by hostnames rather than by IP addresses. DNS domains should not be
confused with Windows NT networking domains. See also DNS server, Network
Information Service (NIS), and ping.
donor system. The computer system you make smaller by removing enclosures, either to
reduce the system or to add the removed enclosures to another target system, using a
process known as system reduction.
double-high ServerNet adapter. A ServerNet adapter that occupies an entire ServerNet
adapter slot in an HP NonStop™ S-series server. Contrast with single-high ServerNet
adapter.
double-high stack. A stack that includes a base, a frame, and two system enclosures.
Contrast with single-high stack.
double-wide plug-in card (PIC). A large-form-factor plug-in card (PIC) that occupies two
adjacent PIC slots within a customer-replaceable unit (CRU). See also single-wide
plug-in card (PIC).
download. The process of transferring software from one location to another, where the
transferring entity initiates the transfer.
download line task. Any task running under the Portable Silicon Operating System (pSOS)
system product, such as a data protocol.
downtime. Time during which a computer system is not capable of doing useful work
because of a planned or unplanned outage. From the end user’s perspective,
downtime is any time a needed application is not available.
downward compatibility. The ability of a requester to operate with a server of an earlier
revision level. In this case, the requester is downward-compatible with the server and
the server is upward-compatible with the requester. Contrast with upward compatibility.
drive. See disk drive, optical disk drive, or tape drive.
dropout. A voltage loss of very short duration (that is, milliseconds).
DSC. See Dynamic System Configuration (DSC).
DSM. See Distributed Systems Management (DSM).