Hadoop Info - Be interview ready - One Active Namenode

4) Interview might ask that why not using two active nodes at a time in a HA cluster . 

You can refer this link : About HA Cluster (High Availability Cluster)

Answer : 

There should be only one active Namenode running in HA cluster .

If there are two active Namenode running in cluster then its lead to corruption of the data. This scenario is termed as split-brain scenario.

To overcome this problem we can use fencing (Its a process of ensuring that only one Namenode remains active)

Hope you like my articles . Please comment and like.