Created on 03-23-2017 07:27 PM
STEPS :
Take a backup of your Ambari database before executing the below command as you are issuing a delete command.
curl --insecure -u admin:<password> -H 'X-Requested-By: ambari' -X DELETE http://<ambari-server-fqdn>:8080/api/v1/groups/<group name you wanted to delete>