IMPORTANT: DO NOT FORGET to backup your Ambari database before executing DELETE API calls. This is tested on Ambari version 2.6.x & 2.7.1. Kindly use these steps on your Test cluster first OR Contact Cloudera Support for more details. Step 1: Take a backup of your Ambari database # mkdir /var/tmp/postgres_backup  # pg_dump -U ambari ambari > /var/tmp/postgres_backup/$(date +"%Y%m%d%H%M%S")_ambari-bkp.sql Step 2: Install jq package (If not available) # rpm -qa | grep jq # yum whatprovides jq # yum install jq -y Step 3: Get All (AD/LDAP) Users & Groups # curl --insecure -u admin:admin -H 'X-Requested-By: ambari' -X GET http://$(hostname -f):8080/api/v1/users?Users/ldap_user=true | jq -r '.items[].Users.user_name' > ambari-ldap-users.txt # curl --insecure -u admin:admin -H 'X-Requested-By: ambari' -X GET http://$(hostname -f):8080/api/v1/groups?Groups/ldap_group=true | jq -r '.items[].Groups.group_name' > ambari-ldap-groups.txt Step 4: Verify Users & Groups that needs to be deleted. If you want to keep some users/groups from the list, you can remove those entries from respective txt files. # cat ambari-ldap-users.txt # cat ambari-ldap-groups.txt Step 5: Remove all AD Users # for my_ldap_user in $(cat ambari-ldap-users.txt) do curl --insecure -u admin:admin -H 'X-Requested-By: ambari' -X DELETE 'http://'$(hostname -f)':8080/api/v1/users/'$my_ldap_user echo 'deleting : ' $my_ldap_user done Step 6: Remove all AD Groups # for my_ldap_group in $(cat ambari-ldap-groups.txt) do curl --insecure -u admin:admin -H 'X-Requested-By: ambari' -X DELETE 'http://'$(hostname -f)':8080/api/v1/groups/'$my_ldap_group echo 'deleting : ' $my_ldap_group done ... View more