NonStop System Glossary

cluster switch layer number

A number in the range 1 through 4 that identifies the position of a cluster switch within a cluster

switch group. See also cluster switch group.

cluster switch logic board

A circuit board that provides switching logic for the HP NonStop ServerNet Switch (model 6780).

The logic board (LB) has a front panel for operator and maintenance functions and is a Class-3

CRU.

cluster switch rack

A mechanical frame consisting of or based on a 19-inch rack that supports the hardware necessary

for a cluster switch group.

cluster switch zone

A pair of X-fabric and Y-fabric cluster switch groups and the ServerNet nodes connected to them.

Up to three zones are possible. The zones, if more than one, are interconnected by interzone

cables, with each cluster switch layer cabled separately from the other layers.

CME

See correctable memory error (CME).

code file

See object code file.

code segment

A segment that contains executable instructions of a program or library to be executed plus related

information. Code segments can be executed and also accessed as read-only data but not written

to by an application program. These read-only and execute-only segments are efficiently shared

among simultaneous executions of that program or library. Therefore, they are read from disk but

are never written back to disk. See also TNS code space.

code set

Codes that map a unique numeric value to each character in a character set, using a designated

number of bits to represent each character. Single-byte code sets use 7 or 8 bits to represent each

character. The ASCII and ISO 646 code sets use 7 bits to represent each character in Roman-based

alphabets; these code sets are very limited and are not appropriate for international use. The

single-byte ISO 8859 code sets use 8 bits to represent each character and can therefore support

Roman-based alphabets and many others including Greek, Arabic, Hebrew, and Turkish. Multibyte

code sets represent characters that require more than one byte, such as East Asian ideographic

characters.

code space

See TNS code space.

COFF

See Common Object File Format (COFF).

cold load

A synonym for system load or load (in the case of single processor load). System load or load is

the preferred term in NonStop system publications.