No NameNode HA™ Architecture
The MapR Distribution of Apache Hadoop is unique because it was designed for high availability. MapR is the only Hadoop distribution with no single points of failure. Other Hadoop distributions have a single NameNode and when the name node goes down, the entire cluster becomes unavailable, requiring minutes or hours to restart the NameNode. With MapR, the NameNode is distributed, so that there is no loss or downtime even in the face of multiple disk or node failures. We call this No NameNode HA.