Odoo's support gave us this response:
Odoo support's response: The master password is related to your PSQL user.
Apologies if my question maybe dumb but I know we have a master password (admin_passwd in config) for managing databases in Odoo (backup, delete, etc.) and each database could have their own password (db_password in config) but does postgres have its own 'master' password?
As a side note, this was installed as enterprise package installer where it uses the default odoo postgres user. I may not have set a password for the database.
Thanks,