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Maven IT suite is run as part of Maven build. Let's call it the "outer build". The outer build may build plugins and some artifacts needed and used by ITs, but may also pre-populate the local repository with needed dependencies (as ITs are cut off from network). The ITs, let's call them "inner build", should run in isolated environment, so not using user settings, possible nor MRM and not being able to reach to remote repositories (aside of those that IT test itself set up).
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