Question: How can you change a MongoDB clusters password?

Answer

To change the password for a user in a MongoDB cluster, you need administrative privileges. This operation involves the use of the db.changeUserPassword() method in the mongo shell. The process is straightforward but requires that you have access to an account with the necessary permissions to update user credentials. Here's a step-by-step guide to changing a user's password:

1. Connect to your MongoDB cluster: Use the mongo shell or any MongoDB client to connect to your database.

2. Select the appropriate database: Switch to the database where the user is defined, typically the admin database for cluster-wide users.

   use admin;

3. Change the user's password: Utilize the db.changeUserPassword() function by specifying the username and the new password.

   db.changeUserPassword('yourUsername', 'newPassword');

   Replace 'yourUsername' with the actual username whose password you want to change and 'newPassword' with the new password.

4. Verify the change (optional): While there's no direct command to verify the new password without trying to reconnect, you can log out and attempt to log back in using the new credentials to ensure the password has been changed successfully.

5. Implement best practices: Ensure the new password is strong and complies with your organization's security policies.

It's important to note that altering user credentials can affect applications and services relying on those credentials. Therefore, plan this change accordingly and update any relevant systems or configurations with the new password to avoid downtime or loss of accessibility.

Lastly, while this guide focuses on changing a password, managing MongoDB users also includes creating, deleting, and assigning roles. Always consider the principle of least privilege when assigning roles to ensure users have only the necessary permissions for their tasks.