Testing part 4: Distributed tests

The blog post by Shlomi Livne focuses on the distributed testing (dtest) framework for ScyllaDB, which extends upon the original dtest project developed for Apache Cassandra. It explains how dtests function as comprehensive black-box tests to ensure ScyllaDB's compatibility with Cassandra by validating cluster operations. The post details various testing scenarios covered by dtest, such as batch operations, paging, TTL, commit logs, server-client notifications, snapshot and restore, and consistency levels. It highlights the importance of automated testing in uncovering bugs, citing examples of issues resolved through dtest, and emphasizes the significance of both unit tests and dtest in ScyllaDB's development process. Additionally, it outlines the plan to add more tests for upgrades and migrations, and discusses the contribution of these tests to the original dtest project, underscoring the collaborative efforts in enhancing ScyllaDB's reliability and functionality.