Reset the database master password on Amazon RDS
If you don’t remember your MariaDB or Aurora database master password on Amazon RDS, you can follow the steps below to reset it to a new value:
Log in to the Amazon RDS dashboard.
Select the “Instances” menu item and then select the MariaDB or Aurora RDS instance you wish to modify.
From the “Instance Actions” menu, click the “Modify” option.
On the resulting page, enter a new password in the “Settings -> New Master Password” field. Leave all other settings as they are.
Scroll down to the end of the page and check the “Apply Immediately” option.
Click the “Continue” button.
Review the submitted modification and click the “Modify DB Instance” button.
The RDS master password for the selected database instance will be modified and you should now be able to access the database server with the new password.