CDS. Control data set. An HSC database containing all configuration and volume information, used by host soft- ware to control functions of automated libraries.
CEI. Configured end item.
CFE. Composite Failure Event. In VTSS, a structure formed for each discrete failure domain.
CFT. Controlled field test.
change journal. In VSM, the record of changes to the functional track directory (FTD) that is kept in nonvolatile storage (NVS) and is then written to the disk arrays (VTSS). VSM uses the change journal to reconstruct the FTD in the event of a failure.
channel. (1) A
channel image. A software image that logically presents itself as a single physical channel, regardless of how the physical connection is made. Each channel image ap- pears to be an independent single physical channel, al- though all channel images on a specific I/O interface share the same facilities and physical paths. A VSM5- VTSS presents up to 16 control unit images to each of 1 to 28 host systems.
channel interface. Controller circuitry that attaches host channels.
check0. An error condition detected within a VTSS pro- cessor card that affects the integrity of the processor. If a second check 0 is detected within the same processor during recovery, the processor
check1. An error condition that affects a control bus or shared memory bus but leaves processor cards function- al. Check1 may affect all processors on a bus, since the bus is locked until the condition is cleared.
check2. An error condition detected in the
checksum. A value that accompanies data transferred between points to ensure the data is transferred correct- ly. Checksum is computed by adding up the bytes or words of a data block. On the receiving end, checksum is computed based on the data received and compared with the value that was sent with the data. If the two numbers match, the data is considered to be correct.
CHPID.
circuit breaker. A switch that automatically interrupts an electrical circuit when there is an overload of current or other abnormal condition.
CKD. See
client. A system which is able to operate independently but has some degree of dependence on another system. Frequently refers to computers on a LAN. A client is a re- cipient of services in a client/server application. Clients can be workstations, PCs, or other servers.
client/server. A system architecture in which one or
more programs (clients) request computing or data ser- vices, such as data storage, processing, or transmission, from another program (server).
clink. clustered link. An ESCON port used to link a mas- ter and slave VTSS in a clustered configuration.
clock speed. In storage systems, the frequency at which the system clock oscillates, as measured in MHz. The faster the clock, the more quickly the system can trans- mit information.
clustering. (1) In VSM, the process of writing a virtual tape volume (VTV) onto two discrete VTSSs. (2) A tech- nique for configuring two or more servers as a single pro- cessing system using software and hardware to allow sharing of storage, processing, and other resources un- der a single management domain, thereby providing greater data accessibility and higher reliability.
CM. Configuration Management. (1) Identification and management of physical product configurations through documentation, records, and data. (2) An organization within Sun responsible for applying these disciplines through a formal EC process.
cold boot. The act of switching a computer, storage sys- tem, etc. Completely off, then switching it back on again. Contrast with warm boot.
cold swap. To remove and replace a system component (typically one such as a logic board that has no redun- dant backup) after system operations have been stopped and power has been disabled. Contrast with hot swap.
collected free space. Array cylinders that are collected and completely free of user data.
collocation. A process that attempts to keep all data be- longing to a single client node on a minimal number of
command line interface. A user interface in which com- mands are keyed onto a command line instead of through a Graphical User Interface. Contrast with GUI.
compaction. The elimination of
compression. The process of encoding data using algo- rithms so that it uses less storage space and/or increas- es the rate, or speed, of data transmission.
Configuration Control Document (CCD). A Sun docu- ment which defines model numbers, family ID codes, feature codes, part numbers, etc. for a specific product, and which identifies the configured end items (CEIs) available for use in the product.
Configuration Status Monitor (CSM). In VTSS, a part of the Failure Management System (FMS) that monitors FRU configurations in the controller, performs FRU vali- dation, and coordinates diagnostic fencing.
controlled
controller. A system control module or storage control unit. Also called a control module or control unit. See al- so disk array controller.
control region. VTSS data path control. Hardware in a multipath controller that is associated with a data path and which transfers data between the cache and disk ar- rays and between cache and host channel(s).
96257 | Sun Confidential: Internal Only | |
| Revision A |
|
