Introduction to NonStop Operations Management

Change and Configuration Management
Introduction to NonStop Operations Management–125507
7-7
Performing Software Changes
Once it is determined that the changes will not affect system security, the staff can
prepare to install the software. The following guidelines can be incorporated into a
preinstallation check list:
•
Determine whether the change requires a new system configuration or
reconfiguration of applications.
•
Determine whether the change requires down time. If so, schedule the down time
with operations and notify users.
•
If an application is distributed across a network, new versions of the application
must be compatible with the old versions at the other nodes or at least be able to co-
exist with the old versions. To solve this problem, use version identifiers that are
imbedded in the requestors, in the servers, and in the messages between the
requestor/server pairs. The requestors and servers can check the version identifiers
to ensure compatibility.
•
Back up all files and programs that will be changed. You might need the backups for
recovery in case the changes do not work.
•
Make sure that the necessary operations staff is available to install the change.
•
Develop a strategy for determining where to locate data files. For example, if an
alternate-key file is accessed frequently by an application, do not locate it on the
same volume as the primary file. If the files are located on the same volume, system
performance might be degraded.
•
Provide the operations staff with the information (documentation, list of file names,
and so on) and tapes it needs to install the changes. You might want to develop a
formal sign-off procedure for handing over all materials to operations.