Testing maintenance operations
While only internal staff perform maintenance operations, they are often among the riskiest on your system. Upgrades and configuration changes are the sources of most outages, in my experience. You’ll need to test the content of each modification, but this section considers changes in the abstract – what should you try for every upgrade?
Real-world example – Which version is that?
I once tested a minor plugin that supported our main product, which was installed locally on a desktop. We shipped the first version, then a couple of maintenance releases. Only after a couple of versions did we realize there was a piece of functionality that we’d missed. Users kept reporting issues that we thought we’d already fixed. Were our fixes failing, or had the user not upgraded? The first question that the support team asked was what version they were running.
Unfortunately, the plugin didn’t report its version number...