What if I don't remember the first time password set of the root/hadoop login. As I am not able to do the admin-password-reset using any of the users as the permission is denied.

[#1]

I tried executing the admin's password reset option..with the two users (raj_ops and maria_dev) but permission denied. And I am not remembering the first time password set by me using the root/hadoop. Please help..

[#2]

What is your current Ambari version?

A. For Ambari 2.6.2.2 and previous versions, follow these steps in the Ambari host:

1. Log in to Postgres database

# 'psql -U ambari ambari'

2. Enter password for 'ambari' database. Default is 'bigdata'. Can be found in this file:

/etc/ambari-server/conf/password.dat

3. In PSQL run the below query:

update ambari.users set user_password='538916f8943ec225d97a9a86a2c6ec0818c1cd400e09e03b660fdaaec4af29ddbb6f2b1033b81b00' where user_name='admin'

4. Quit PSQL

5. Restart Ambari server

ambari-server restart

This will reset the admin account back to the password of 'admin'.

Steps taken from:

https://community.hortonworks.com/questions/449/how-to-reset-ambari-admin-password.html

B. For Ambari 2.7.x you can follow steps mentioned in this article:

[Ambari-2.7.0] How to Reset Ambari Admin Password from Database if you forget it ?

Hope it helps.