Importance of Fallback Testing

Fall backtesting is equal to test the contingency plan for reverting to the old system or to an alternative emergency solution in the event of a failure of the new system.

To test that when the new build is not installed properly at client side it should automatically be revert back to the previous build. We should verify that the old system can tolerate changes that were made by the new system after recovery.

We should always plan to have a backout path when installing new software by identifying and installing any service required to support back out. For example:

When the new build is installed in production and it made some changes in data structures.

Rollback the build manually to test fallback.

These changes might not be compatible with the old release. Scripts should be written to support the rollback of all changes done while installing the new build.

Fallback testing is the ability of an application to transfer processing to the backup system without disrupting customer services.

Fallback testing also refers to a condition to trigger a switch in real time from a primary server to a backup server so that the connected user base impact is minimized.

The primary reason for fallback is build failure but there are some other reasons which case fallback to happen in the real scenario.

Other Reasons why Fallback is required:

• New functionality is difficult to understand for old customers.

• Changes are not acceptable by the product manager.

• New functionality is not documented properly in a usable manner and not accessible to Staff.

• Customers are unaware of new changes.

• New changes are of minimal use to customers.

• Staff is incapable of operating the new processes.

Fallback is done at a system level but not at the element or feature level.