Sam R. Alapati has been working with various aspects of the Hadoop environment for the past six years. He is currently the principal Hadoop administrator at Sabre Corporation in Westlake, Texas, and works on a daily basis with multiple large Hadoop 2 clusters. In addition to being the point person for all Hadoop administration at Sabre, Sam manages multiple critical data-science- and data-analysis-related Hadoop job flows and is also an expert Oracle Database Administrator. His vast knowledge of relational databases and SQL contributes to his work with Hadoop related projects. Sam’s recognition in the database and middleware area includes having published 18 well-received books over the past 14 years, mostly on Oracle Database Administration and Oracle Weblogic Server. His experience dealing with numerous configuration, architectural, and performance-related Hadoop issues over the years led him to the realization that many working Hadoop administrators and developers would appreciate having a handy reference such as this book to turn to when creating, managing, securing and optimizing their Hadoop infrastructure.