We currently allow users to define commands which acquire sensitive configuration material, like passwords. However, not all environments have available secrets management solutions.

Ops Manager has provided something called credentialstool which manages a local file containing an encryption key, which is used to decrypt configuration entries.

A similar mechanism, or especially a compatible mechanism, would be convenient for these environments. This would allow system administrators to define keys and restrict access to them with filesystem permissions. Casual viewers of the MongoDB configuration file would be able to perform diagnostics, but wouldn't have the ability to learn protected values.