What are you trying to test with them? As depending on what you are doing and at what stage of development you doing the testing will depend what it is. BTW there can be are often are functional unit tests, it is the performance or "non-functional" aspects of unit testing that are missed in organisations, in my experience.
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An example case would be having a DB server offline where the installer should be accessing it at that time or the user trying to install/access the database has no permission. In my experience, these kinds of test are done manually in the company I worked for. What type of test case does this fall? Acceptance? Functional? Regression? Also, how are these addressed in automated testing?