@Theyaa Matti
Please try these steps:
1). In Ambari, HDFS > Configs > Advanced > Custom hdfs-site, Add the following properties. Herer "My-NN-HA" is the Cluster Service name
dfs.namenode.servicerpc-address.My-NN-HA.nn1=erie1.example.com:8021
dfs.namenode.servicerpc-address.My-NN-HA.nn2=erie2.example.com:8021
ipc.8020.callqueue.impl=org.apache.hadoop.ipc.FairCallQueue
ipc.8020.backoff.enable=true
ipc.8020.scheduler.impl=org.apache.hadoop.ipc.DecayRpcScheduler
ipc.8020.scheduler.priority.levels=3
ipc.8020.decay-scheduler.backoff.responsetime.enable=true
ipc.8020.decay-scheduler.backoff.responsetime.thresholds=10,20,30
2). After the mentoined changes you might get the following error in your Logs while starting the servivce. Also the NameNodes might be moved to "StandBy" (Both)
2017-06-20 06:38:14,116 WARN ha.EditLogTailer (EditLogTailer.java:triggerActiveLogRoll(276)) - Unable to trigger a roll of the active NN
org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.ipc.StandbyException): Operation category JOURNAL is not supported in state standby
at org.apache.hadoop.hdfs.server.namenode.ha.StandbyState.checkOperation(StandbyState.java:87)
at org.apache.hadoop.hdfs.server.namenode.NameNode$NameNodeHAContext.checkOperation(NameNode.java:1979)
OR
java.lang.RuntimeException: Mismatched address stored in ZK for NameNode
3). So you will need to run the following command. Stop the ZKFC processes on both NameNodes to reset the ZKFC state in ZooKeeper
hdfs zkfc -formatZK
4). Restart the ZKFC servers and then check the grafana / AMS after 2-3 minutes time..

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