This Article is intended to Ambari Administrators who will be managing ambari . And for the steps mentioned below, you need access to ambari Server and ambari database. For Ambari versions below ambari-2.6.2.2 refer to comments here : https://community.hortonworks.com/questions/449/how-to-reset-ambari-admin-password.html This article is for Ambari-2.7.0.0 and above. Problem Statement: you have changed the password of the admin user in UI and now you forgot the password. you want to reset the admin password. Steps 1) Stop ambari server ambari-server stop 2) login to your database (default password will be bigdata) psql -U ambari ambari or ( for mysql) mysql -U ambari -D ambari 3) execute the command : update user_authentication set authentication_key='538916f8943ec225d97a9a86a2c6ec0818c1cd400e09e03b660fdaaec4af29ddbb6f2b1033b81b00' where user_id in (select user_id from users where user_name='admin'); 4) exit the database and restart ambari-server ambari-server start Now password is reset to default one(ie admin) and you can login to ambari-server using admin/admin . Hope this helps. ... View more

Apache Ambari is a tool for provisioning, managing, and monitoring Apache Hadoop clusters. Ambari provides central management for starting, stopping, and reconfiguring Hadoop services across the entire cluster. Ambari-server Sends Commands to Ambari-agent for such operations in JSON format which is saved in /var/lib/ambari-agent/data folder. these json (command-*.json, status_command.json) Files may contain usernames and passwords which is required for few services at startup Currently the command JSON files are stored on disk in /var/lib/ambari-agent/data. These files may be cleared out over time, but there is a need to have them removed as soon as they are no longer needed. Ambari-2.7.0 Provides a provision for deleting the command JSON files once Operation is successful to reduce the risk of leaking sensitive data stored at plaintext in the command JSON files. More Details about this can be found at the Apache JIRA: https://issues.apache.org/jira/browse/AMBARI-24228 How To Enable this feature in Ambari-agent Steps ******* Stop Ambari-agent ambari-agent stop 2. edit the file located at /etc/ambari-agent/conf/ambari-agent.ini [root@akhiln conf]# vi /etc/ambari-agent/conf/ambari-agent.ini 3. Add below line under [agent] heading and save the file command_file_retention_policy=remove 4. Start ambari agent ambari-agent start Note : Possible Options for this tag are: keep No automatic removal is performed This is the default behavior remove The command JSON file are remove as soon as the command completes remove_on_success The command JSON files are remove as soon as the command successfully completes The command JSON files are not removed on failure conditions Please Note this feature is as of now available from Ambari-2.7.0 if you need to backport this feature to your version and you are under hortonworks subscription please contact hortonworks support. ... View more