ndb kernel has the ability to add bits of code like: CRASH_INSERTION((10021)); into code and have a test suite make ndbd crash at this point. You can also add if(ERROR_INSERTED(10023)) to simulate an error in a specific part of the code. This is used extensively in a bunch of the autotest tests to simulate various failures and especially in the code designed to recover from them. We currently don't have these in ndb_mgmd and testing is subsequently manual work alongside such tests as "did the cluster start and nodes connect okay" This WL is to add CRASH_INSERTION and ERROR_INSERTED into ndb_mgmd so that more automated testing can be devised. There also needs to be a method of inserting an error and getting notification on when this point has been reached so that a test suite could (for example) unplug the node from the network or crash the box. This could come in the form of a mgmapi call for "wait for error". The bulk of the time will be spent writing the automated tests and putting the crash and error insertion into existing code.