2.3.Maintenance Testing
There are different categories of maintenance, it can be corrective, adaptive to changes in the
environment or improve performance or maintainability (see ISO/IEC 14764 for details), so maintenance
can involve planned releases/deployments and unplanned releases/deployments (hot fixes). Impact
analysis may be done before a change is made, to help decide if the change should be made, based on
the potential consequences in other areas of the system. Testing the changes to a system in production
includes both evaluating the success of the implementation of the change and the checking for possible
regressions in parts of the system that remain unchanged (which is usually most of the system).
The scope of maintenance testing typically depends on:
• The degree of risk of the change
• The size of the existing system
• The size of the change
The triggers for maintenance and maintenance testing can be classified as follows:
• Modifications, such as planned enhancements (i.e., release-based), corrective changes or hot
fixes.
• Upgrades or migrations of the operational environment, such as from one platform to another,
which can require tests associated with the new environment as well as of the changed software,
or tests of data conversion when data from another application is migrated into the system being
maintained.
• Retirement, such as when an application reaches the end of its life. When a system is retired, this
can require testing of data archiving if long data-retention periods are required. Testing of restore
and retrieval procedures after archiving may also be needed in the event that certain data is
required during the archiving period.