Teradata recommends mapping all users to a defined routing rule using user mapping. Business Continuity Manager includes a default routing rule that is used when a user is not mapped to a defined routing rule. After Business Continuity Manager is installed, the DefaultRouting rule is set to Reject. This is a best practice to make sure that any user not mapped to a user mapping is blocked.
You can update the default routing rule to choose a different default behavior. For example, you can set the default to a passive, single-system routing rule.
When a user is mapped to the default routing rule, an alert informs the DBA. You can disable this alert if this is the intended behavior. However, this is not a recommended best practice.