The Hadoop Data Nodes Layer

Using the tests mapped to this layer, you can:

• Identify overloaded and slow DataNodes in the cluster;
• Be alerted if any DataNode does not send heartbeats to the NameNode or is taking too much time to do so;
• Pinpoint DataNodes that are not effectively utilizing their off-heap memory;
• Monitor block reporting and cache reporting operations of each DataNode, and capture abnormalities (if any)

Figure 1 : The tests mapped to the Hadoop Data Nodes layer