Maintenance Testing

Maintenance Testing

Software Acceptance Testing

Terms

Impact analysis, maintenance testing

Background

Once deployed, a software system is often in service for years or decades. During this time the system, its configuration data, or its environment are often corrected, changed or extended. The planning of releases in advance is crucial for successful maintenance testing. A distinction has to be made between planned releases and hot fixes. Maintenance testing is done on an existing operational system, and is triggered by modifications, migration, or retirement of the software or system.

Modifications include planned enhancement changes (e.g., release-based), corrective and emergency changes, and changes of environment, such as planned operating system or database upgrades, planned upgrade of Commercial-Off-The-Shelf software, or patches to correct newly exposed or discovered vulnerabilities of the operating system.

Maintenance testing for migration (e.g., from one platform to another) should include operational tests of the new environment as well as of the changed software. Migration testing (conversion testing) is also needed when data from another application will be migrated into the system being maintained.

Maintenance testing for the retirement of a system may include the testing of data migration or archiving if long data-retention periods are required.

In addition to testing what has been changed, maintenance testing includes extensive regression testing to parts of the system that have not been changed. The scope of maintenance testing is related to the risk of the change, the size of the existing system and to the size of the change. Depending on the changes, maintenance testing may be done at any or all test levels and for any or all test types. Determining how the existing system may be affected by changes is called impact analysis, and is used to help decide how much regression testing to do. The impact analysis may be used to determine the regression test suite.

Maintenance testing can be difficult if specifications are out of date or missing, or testers with domain knowledge are not available.