Zookeeper is an open-source software tool used to coordinate distributed applications. It is used as a centralized service for maintaining configuration information, naming, providing distributed synchronization, and group services. Zookeeper provides a simple interface for applications to use, and its reliability and scalability make it a popular choice for many

Apache Nifi

Information Source: https://projects.apache.org/project.html?accumulo The Apache Accumulo sorted, distributed key/value store is based on Google's BigTable design. It is built on top of Apache Hadoop, Apache Zookeeper, and Apache Thrift. It features a few novel improvements on the BigTable design in the form of