The “DRBDv8 Regression Testsuite” was designed to enforce rare, but fatal situations in the DRBDv8 pre-release. The testsuite executes and verifies predefined (but fully configurable) testcases by issueing the given commands on two or more nodes of a DRBD cluster. Before each testcase the so-called agents, who process the commands on local nodes, synchronize themselves so that resources can be accessed at the very same time.
The testsuite was developed in Perl in cooperation with Linbit. Two of our first three testcases were able to trigger an unhandled excecption in the DRBDv8 pre-release; and were fixed in the final release, of course.