Big Data is the latest hype in the security industry. We will have a closer look at what big data is comprised of: Hadoop, Spark, ElasticSearch, Hive, MongoDB, etc. We will learn how to best manage security data in a small Hadoop cluster for different types of use-cases. Doing so, we will encounter a number of big-data open source tools, such as LogStash and Moloch that help with managing log files and packet captures. As a second topic we will look at visualization and how we can leverage visualization to learn more about our data. In the hands-on part, we will use some of the big data tools, as well as a number of visualization tools to actively investigate a sample data set.