To simplify the development process, VoltDB predefines two roles for you when you enable security: administrator and user. Administrator has ADMIN permissions: access to all functions including interactive SQL queries, DDL, system procedures, and user-defined procedures. User has SQL and ALLPROC pemissions: access to ad hoc SQL and all default and user-defined stored procedures.
These predefined roles are important, because when you start the database there is no schema and therefore no user-defined roles available to assign to users. So you must always include at least one user who is assigned the Administrator role when starting a database with security enabled. You can use this account to then load the schema — including additional security roles and permissions — and then update the configuration to add more users as necessary.