Improve error messages in auth

**Feature request**
It would be great to have backup for components.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_backup` with default `false`.

No files or tests are named. Start by locating the authentication configuration and the component startup or recovery paths, then clarify how backup should work and which components it covers; done should include an `enable_backup` option defaulting to `false` and verified behavior for the stated production use case.

Written by the indexing model from the issue text.