How Do I Modify the HDFS Active/Standby Switchover Class?

If the org.apache.hadoop.hdfs.server.namenode.ha.AdaptiveFailoverProxyProvider class is unavailable when a cluster of MRS 3.x connects to NameNodes using HDFS, the cause is that the HDFS active/standby switchover class of the cluster is configured improperly. To solve the problem, perform the following operations: