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Begin with a patch that adds new system test directory as a sibling of the old one. This directory will have bootstrap scripts for Vagrant, a few specific 'services' such as KafkaService and ZookeeperService, and a few new system tests.
Make sure provisioning and setup scripts are in a state where everyone in the community can reasonably easily run the full test suite on their own testbed.
Once test coverage with new tests is roughly a superset of old system test coverage, old system_tests directory will be removed. Roadmap for this is here.
Existing system_tests roughly cover the following, and new tests should cover these categories before deleting the existing directory:
Producer performance (producer_perf, which has wrappers for kafka.tools.ProducerPerformance)
Various correctness tests in the face of broker failover (replication_testsuite)
Consumer offset management in the face of consumer failure (offset_management)
Mirror maker tests which propagate data across broker clusters in the face of various types of failure.
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