Availability Guide for Change Management

Introduction to Change Management
Availability Guide for Change Management–125506
1-5
Meeting the Goals of Change Management
Installing and Reconfiguring Communications Subsystems
In the Tandem environment, a software product that provides users with access to a set
of communications services is called a communications subsystem. Making changes
to a communications subsystem can involve adding new communications lines or
devices to accommodate business growth, connecting new systems to the network, or
reconfiguring certain configuration attributes.
Section 5, “Making Communications Subsystem Changes Online,” identifies common
communications subsystem changes and describes the tools you can use to perform
those changes while your NonStop system remains operational.
Installing and Reconfiguring Applications
This manual does not discuss how to make changes to customer applications.
Meeting the Goals of Change Management
The main goal of change management is to minimize the impact of change on system
and application availability while successfully migrating your system or application
from one stable configuration to another. Successful change management also ensures
that system and application security is maintained during the change process.
You can meet the goals of change management by:
•
Performing changes online
•
Reducing the time required for planned outages
Making Changes Online
Being able to make changes online is one way you can reduce—or even eliminate—
system and application downtime caused by change. Online change is any change that
can be performed while your NonStop system is still operational.
The following sections describe how to make changes online:
•
Section 3, “Making System Software and Hardware Changes Online,” explains how
to make changes to your system software and hardware online.
•
Section 4, “Making Application Subsystem Changes Online,” explains how to make
changes to NonStop TS/MP, NonStop SQL/MP, and NonStop TM/MP online.
•
Section 5, “Making Communications Subsystem Changes Online,” explains how to
make changes to communications subsystems online.
In some situations, online changes may temporarily affect application availability. For
example, altering the characteristics of a communications line may temporarily affect
applications that use that communications line. Sections 3, 4, and 5 describe online
changes that affect application availability and how you can reduce the impact of these
changes on application availability.