Availability Guide for Change Management

Change Control
Availability Guide for Change Management–125506
2-3
Phase 1—Definition and Documentation
Phase 4—Verification. In this phase, the person or group responsible for change
control makes sure that the system is running correctly and reviews the change-control
process to make any necessary improvements.
The following paragraphs provide guidelines for accomplishing each phase of the
change-control process. If you need tools for use in change control, your Tandem
representative can direct you to the Tandem Alliance Program companies that offer
change-control tools. Third-party change-control tools are also listed in the Alliance
Solutions & Services Directory, which can be found on Tandem’s Web page at:
http://www.tandem.com/MENU_PGS/ALLIANCE/ALL_SSD.HTM.
Phase 1—Definition and Documentation
The first phase of the change-control process consists of determining what is to be
changed and then formally defining the proposed change. Change can come from a
variety of sources and can be caused by a variety of factors. Some of the items that can
be changed in any production environment include hardware, communications lines,
firmware, operating system code, application subsystems, application software code, and
recovery and backup procedures. Section 1, “Introduction to Change Management,”
describes common changes and their causes.
During the definition and documentation phase, you should collect the following
information about the proposed change:
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A detailed description of the proposed change
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The deadline for the change
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A list of files and documentation that must be changed
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Why the proposed change is necessary
Some organizations use change-request forms to help define and document changes.
Change-request forms are standardized online or hard-copy forms filled out by people
requesting changes and presented to the person or group in charge of change control.
Using a Planned Outage Request Form
The impact of change on system and application availability can be nonexistent or can
require your system or application to be shut down. For changes that affect system or
application availability, a planned outage request form can be used to gather information
about the change.
A planned outage request form helps set expectations and enables managers to
understand the reasons for planned outages. A planned outage request form also
provides historical data that can be used for trend analysis, which in turn can be used to
determine where improvement opportunities exist. Trend analysis can help managers
evaluate the effectiveness and accuracy of change plans, recovery plans, and downtime
estimates.
A planned outage request form should include the following types of information:
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The date and time of the planned outage.