Managing High Availability
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Re-enable the standby NameNode

To re-enable the standby NameNode:

  1. Run the following commands on the Ambari Server host:
    curl -u [AMBARI_USER]:[AMBARI_PW] -H "X-Requested-By: ambari" -i -X PUT -d '{"RequestInfo":{"context":"Enable Secondary NameNode"},"Body":{"HostRoles":{"state":"INSTALLED"}}}'[AMBARI_PROTO]://localhost:[AMBARI_PORT]/api/v1/clusters/[CLUSTER_NAME]/hosts/[SECONDARY_NAMENODE_HOSTNAME}/host_components/SECONDARY_NAMENODE
  2. Analyze the output.
  3. If this returns 200, proceed to delete all JournalNodes.
  4. If this input returns the value 202, wait a few minutes and then run the following command:
    curl -u [AMBARI_USER]:[AMBARI_PW] -H "X-Requested-By: ambari" -i -X GET "[AMBARI_PROTO]://localhost:[AMBARI_PORT]/api/v1/clusters/
  5. Wait for the response "state" : "INSTALLED" before proceeding.
Delete all JournalNodes.