R

RAC

Oracle 9i Real Application Cluster.

RAM

random access memory.

Reliability

An abstract term defined as the probability that a product or system performs its intended function for a specified time period when operating under normal environmental conditions. Reliability differs from availability in that reliability involves only one event, failure, whereas availability takes into account two events: failure and recovery. A system can be highly available yet experience frequent periods of inoperability as long as the length of each period is short.

RBAC

role-based access control.

RBD

reliability block diagram.

RDBMS

relational database management system.

RM-API

Resource Management API.

RM

replica managers.

RMA

replica manager agents.

RMM

replica manager manager.

RPN

risk priority number.

RSC

remote service controller.

RSM

Remote Shared Memory.

RTR

resource type registration.

RTS

redundant transfer switch.

RTU

redundant transfer unit.