An Introduction to Security in a CSM 1.3 for AIX 5L Environment

6 An Introduction to Security in a CSM 1.3 for AIX 5L Environment

1.2.1 Reliable Scalable Cluster Technology (RSCT)

RSCT is the “glue” that holds the nodes together in a cluster. It is a group of

low-level components that allow clustering technologies, such as High

Availability and General Parallel File System (GPFS) to be built easily.

RSCT technology was originally developed by IBM for RS/6000 SP systems

(Scalable POWERparallel). As time passed, it became apparent that these

capabilities could be used on a growing number of general computing

applications, so they were moved into components closer to the operating

system (OS), such as Resource Monitoring and Control (RMC), Group Services,

and Topology Services.

The components were originally packaged as part of the RS/6000 SP Parallel

System Support Program (PSSP) and called RSCT. RSCT is now packaged as

part of AIX 5L Version 5.1 and later.

RSCT is also included in Cluster Systems Management for Linux. Now, Linux

nodes (with appropriate hardware and software levels) running CSM 1.3 for

Linux can be part of the management domain cluster 1600, and RSCT (with

RMC) being the common interface for the clustering. For more information about

this heterogeneous cluster, see

An Introduction to CSM 1.3 for AIX 5L,

SG24-6859

.

RSCT includes these components:

򐂰 Resource Monitoring and Control (RMC)

򐂰 Resource managers (RM)

򐂰 Cluster Security Services (CtSec)

򐂰 Group Services

򐂰 Topol ogy Ser vi ces

1.2.2 Resource Monitoring and Control (RMC)

RMC is the scalable, reliable backbone of RSCT. It runs on a single system or on

each node of a cluster, providing a common abstraction for the resources of the

cluster. In a cluster, the RMC framework allows a process on any node to

perform an operation on one or more resources on any other node inside the

cluster.

As the name implies, RMC

monitors

resources (disk space, CPU usage,

processor status, application processes, and so on) and

controls

the system by

performing actions in response to defined conditions.

For example, RMC can be configured to expand a file system automatically if its

usage exceeds 95%. RMC enables users to configure response actions or run