Delete all JournalNodes
You may need to delete any JournalNodes.
Check to see if you need to delete JournalNodes, on the Ambari
Server host:
curl -u [AMBARI_USER]:[AMBARI_PW] -H "X-Requested-By: ambari" -i -X GET
[AMBARI_PROTO]://localhost:[AMBARI_PORT]/api/v1/clusters/[CLUSTER_NAME]/host_components?HostRoles/component_name=JOURNALNODE
If this returns an empty items array, you can go on to delete the additional NameNode. Otherwise you must delete the JournalNodes.