Follow these procedures to update the master user's password:
The Amazon RDS console should now be open.
Databases to choose from
Choose Modify after you've selected the RDS DB instance.
If you're using Aurora, expand the cluster and select the instance you'd like to change. Select Modify from the drop-down menu that appears.
In the New Master Password section, enter the master user password that you want to use.
Note that the password change is asynchronous and takes effect immediately. The Apply Immediately setting is ignored in this update.
After that, select Modify DB Instance from the drop-down menu.
Resetting-master-credentials appears in the Status field of your RDS DB instance on the RDS dashboard. The Status column changes to Available once the adjustment is completed.
Hope this helps!
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