Introduction to NonStop Operations Management

Contingency Planning
Introduction to NonStop Operations Management–125507
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Computer Center Location and Facilities
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Network and system configurations
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Data recovery and integrity
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Data archiving procedures
Computer Center Location and Facilities
Review Section 3, “The Operations and Support Areas,” to ensure that your computer
center and systems are protected. If you follow the guidelines in Section 3, you can
avoid many disasters such as flooding, fires, and illegal access—or at least minimize the
damage that such adversities would cause.
Security
Security can help you protect all areas of the data processing center, including the
operations and support staff, the data processing center, equipment, material and
supplies, software applications, and data. Review Section 9, “Security Management,” for
guidelines on developing a security policy and security procedures.
Controlling access to all areas of the operation, including the software, can also help you
protect your operations. For example, you can limit access to the computer room by
locating frequently used devices, such as printers, away from the room and by not
posting signs that indicate the location of the computer facilities.
Preventive Maintenance and System Monitoring
Business-threatening disasters can occur when regular preventive maintenance and
system monitoring are not performed. Review Section 3, “The Operations and Support
Areas,” to ensure that maintenance guidelines are followed, and Section 5, “Production
Management,” to ensure that system-monitoring tasks are performed.
System and Network Configuration
The Tandem system and network architecture helps you avoid disasters related to
hardware failures. All systems have a primary and backup processor, dual-ported
controllers, dual-ported disks, and the option of having mirrored disks.
Usually, disks that contain critical data are mirrored (for example, the operating system
data is usually located on a mirrored disk volume called $SYSTEM). If one disk of the
volume fails, the information is not lost: the mirror volume is still operational, and
programs continue to write data to it without interruption. When the failed disk is
restored, all data is copied back onto it from the mirror volume while transaction
processing continues, and the mirrored operation resumes in full.
The Expand data communications network extends fault-tolerant operations to networks
of geographically distributed computer systems. You can use Expand to connect Tandem
NonStop systems at different locations to form a single network in which
communications paths are constantly available, even in the event of a single line or
component failure. If one path between nodes fails, Expand automatically reroutes and
(when appropriate) retransmits messages using the next-best available path.